Abstract

Is China likely to intervene if war breaks out on the Korean Peninsula, and if so, does Beijing have the willingness and capabilities to deal safely with North Korea's nuclear program? Securing and destroying Pyongyang's nuclear weapons would be the United States’ top priority in a Korean contingency, but scholars and policymakers have not adequately accounted for the Chinese military's role in this mission. China's concerns about nuclear security and refugee flows, its expanding military capabilities to intervene, and its geopolitical competition with the United States all suggest that China is likely to intervene militarily and extensively on the Korean Peninsula if conflict erupted. In this scenario, Chinese forces would seek to gain control of North Korea's nuclear facilities and matériel. For the most part, China has the capabilities to secure, identify, and characterize North Korean nuclear facilities, though it exhibits weaknesses in weapons dismantlement and nonproliferation practices. On aggregate, however, Chinese troops on the peninsula would be beneficial for U.S. interests and regional security. Nevertheless, to mitigate the risks, the United States should work with China to coordinate their movements in potential areas of operation, share intelligence, and conduct combined nuclear security training.

Introduction

For decades, North Korea (the Democratic People's Republic of Korea, or DPRK) has posed one of the most complicated security challenges confronting the United States. The security challenge has three primary dimensions. First, North Korea continues to pose a conventional threat to South Korea (the Republic of Korea, or ROK), an important U.S. ally. A major conventional war on the Korean Peninsula would cause much devastation and loss of life. Second, the North Korean regime could collapse, creating chaos and instability on the peninsula and potentially triggering intervention by the United States and China. Third, North Korea has become a nuclear weapons state and is developing an arsenal of intercontinental ballistic missiles that could deliver nuclear warheads to targets in the continental United States.

In 2017, the North Korean security challenge came to the fore, as President Donald Trump and Korean leader Kim Jong-un traded threats and insults. Trump called Kim a “Rocket Man” on a “suicide mission” and warned that the United States would rain “fire and fury like the world has never seen” on North Korea. Kim referred to Trump as a “mentally deranged U.S. dotard” and threatened to “turn Washington, the stronghold of American imperialists and the nest of evil, and its followers, into a sea of fire.”1 In addition to the escalating war of words, North Korea conducted multiple tests of nuclear weapons and ballistic missiles, including missiles that apparently had a range sufficient to reach the United States.2

In June 2018, tensions between the United States and North Korea were at least temporarily ameliorated when Trump and Kim held a summit meeting in Singapore. The summit raised hopes that the United States and North Korea would avoid steps that could lead to war and that the North Korean nuclear threat would be resolved through further negotiations. The two leaders seemed to establish a personal rapport. They also signed a joint statement that committed North Korea to “work toward complete denuclearization of the Korean Peninsula” and pledged joint efforts to “build a lasting and stable peace regime on the Korean Peninsula.”3

In the aftermath of the Trump-Kim summit, however, North Korea's actions raised doubts about its willingness to eliminate its nuclear weapons and ballistic missiles. Although North Korea apparently had demolished its nuclear test site in May 2018 and began dismantling a missile-engine test site in July 2018, reports from the U.S. intelligence community and independent observers suggested that Pyongyang was continuing to build intercontinental ballistic missiles and was preparing to conceal its nuclear assets and activities.4

Moreover, the post-summit diplomatic interactions between the United States and North Korea suggested that even if there were progress toward the elimination of North Korea's nuclear weapons, it might be far less rapid and complete than the United States had hoped. After U.S. Secretary of State Mike Pompeo held two days of reportedly fruitless talks in Pyongyang in July 2018, North Korea denounced the United States for making a “unilateral and gangster-like demand for denuclearization.”5 In August 2018, the North Korean foreign minister privately accused the United States of retreating from the agreement that had been reached at the Trump-Kim summit.6

The uncertain progress of U.S.-North Korean negotiations and disturbing signs of activity from North Korea's nuclear complex suggest that Pyongyang has no plans to give up its nuclear arsenal. Even if the United States and North Korea agree to denuclearize the Korean Peninsula, North Korea may surreptitiously violate the agreement or renege on its commitments. The United States may contemplate military force to disarm North Korea or to take control of North Korea's nuclear arsenal if the Kim regime collapses or the Korean Peninsula otherwise plunges into chaos. In any of these scenarios, China is likely to play a critical role. As a neighbor of North Korea, China has the most at stake and the greatest capability to intervene. This article considers what China might do in various scenarios involving conflict, chaos, and nuclear weapons in North Korea and how the United States and China might act to further their shared interests.

North Korea's pursuit of nuclear weapons and delivery systems has been a thorn in the side of U.S.-China relations for more than two decades. U.S. policymakers and experts agree—halting North Korea's nuclear and missile program is the top priority for the U.S.-China bilateral relationship.7 Secretary of Defense James Mattis affirmed in June 2017 the United States and China's “strong commitment to cooperate … to realize our shared goal of denuclearization of the Korean Peninsula,” adding that “China's end state on the Korean Peninsula in terms of nuclear weapons is the same as ours.”8 After another DPRK nuclear missile test in September 2017, President Trump also noted that Pyongyang “continue[s] to be very hostile and dangerous to the United States … and a great threat … to China, which is trying to help but with little success.”9

Although the United States seeks to work with China diplomatically on the North Korea nuclear issue, Washington does not coordinate with Beijing in preparing for contingencies involving the end of the North Korean regime.10 If the Kim regime collapsed or if a war broke out on the peninsula, the United States would support its South Korean ally in conducting stability operations, defeat any remaining military resistance, and eliminate North Korea's conventional and nuclear weapons.11 Of all these missions, the U.S. government considers securing and destroying North Korea's weapons of mass destruction (WMD) and associated facilities “the most critical U.S. task.”12 Pyongyang's November 2017 test of an intercontinental ballistic missile that potentially could strike major U.S. cities, including Los Angeles and Chicago, only raises the importance of controlling, defeating, disabling, and disposing of weapons of mass destruction with respect to other potential combat missions.

This mission is currently referred to as WMD-C3D (WMD control, defeat, disable, and dispose)—an update in terminology to the previous mission of WMD-Elimination (WMD-E), which refers to a set of military operations designed “to systematically locate, characterize, secure, disable, and/or destroy a state or nonstate actor's WMD programs and related capabilities in hostile and uncertain environments.”13 The WMD-C3D mission includes preventing the looting or capture of WMD and related materials, as well as rendering safe or destroying weapons, materials, agents, their means of production, and related delivery systems. This mission supports the broader counter-WMD strategy of seeking to ensure that “no new actors obtain WMD, those possessing WMD do not use them, and if actors use WMD, their effects are minimized.”14

One issue, however, has not been addressed adequately in the scholarly or policy literature: how China could affect the ability of the United States to secure and eventually eliminate North Korean nuclear weapons, materials, and facilities in a contingency.15 Would China be likely to intervene if war broke out on the peninsula, and, if it did, how would it deal with North Korea's nuclear program? Even if China were willing to conduct its own WMD-C3D mission on the peninsula, does the People's Liberation Army (PLA) have the capabilities to do so?16

Given the heightened risks, an in-depth understanding of China's intentions and capabilities with respect to each step of this mission is necessary and timely. A prominent public intellectual, Jia Qingguo, argued that China must be prepared to discuss contingency plans with the United States and South Korea, and that the issue at the top of Beijing's list should be who would control North Korea's nuclear weapons arsenal.17 Noting that this responsibility would be costly, Jia nevertheless argues that, “on balance, China may wish to take care of the nuclear weapons itself,” because “China may have a problem with the U.S. military crossing the 38th parallel, reviving memories of the Korean War in the early 1950s.”18

To evaluate China's intentions and capabilities regarding a contingency on the Korean Peninsula, I relied on a variety of sources. First, I conducted a critical reading of Chinese authoritative writings. The topic of North Korea, particularly its possible collapse, is politically sensitive in China, so government officials and scholars are extremely cautious when addressing this topic. As a result, relevant material is limited, but highly accurate—Chinese publications would not risk spreading ideas that challenge the Party line. Second, I interviewed two dozen scholars, think tank researchers, scientists, and military officials in China and discussed the issue with experts at a nuclear workshop and a Track 1.5 meeting on nuclear issues (both in Beijing). Third, this article is informed by a series of workshops, meetings, and conversations with the individuals most closely involved with the WMD-C3D mission at Special Operations Command Pacific, U.S. Forces Korea, the Pentagon, the National Ground Intelligence Center, the Asia-Pacific Center for Security Studies, and the National Defense University.19

I argue not only that Chinese intervention in a Korea contingency is likely, but that Chinese troops on the peninsula would be beneficial, on aggregate, for U.S. interests and regional security. Given its geographic, logistical, and force posture advantages, China would likely reach North Korea's nuclear facilities first. China would be intervening not to support the North Korean regime, but rather to achieve its own strategic objectives—one of which is to prevent the use of nuclear weapons or a nuclear accident on the peninsula. Nuclear weapons in the hands of the Chinese would mean that the North Koreans could not use them, an obvious plus.20 China also has the conventional capabilities, particularly the manpower, to secure all of North Korea's nuclear sites, which would allow the United States to focus its more limited manpower on warfighting.21

Conceding part of the WMD-C3D mission to China would not be without drawbacks. China's nuclear weapons dismantlement and nonproliferation capabilities have certain limitations. Cooperation with the United States and the international community, however, could help to mitigate them, an option that my Chinese interlocutors have stated that Beijing might consider. The biggest trade-off would come after the conflict, when China would seek to use the leverage it gained in controlling North Korean territory and nuclear facilities to ensure that the terms of reunification were more favorable to Beijing than to Washington. But given the limited ability of the United States to conduct a WMD-C3D mission in North Korea or to deter Chinese involvement there, coupled with the risk of war with China if it tried, the operational benefits to the United States would outweigh the strategic costs.

Understanding how China's interests and capabilities with respect to the Korean Peninsula have changed under Chinese President Xi Jinping, and their likely impact in a North Korean contingency involving WMD-C3D, fills three gaps in the security studies literature. First, it provides a framework based on the intervention literature for understanding why third parties may intervene in a costly conflict. Thus, it highlights the need for returning to a focus on major power competition as an impetus for intervention in intrastate and interstate war, in addition to humanitarian missions. Second, it is the first to lay out in detail Chinese interests and capabilities in a potential mission in North Korea.22 Third, the article adds to the growing literature on Chinese military capabilities by providing the first scholarly assessment of Chinese WMD-C3D capabilities, which may become increasingly important as the PLA expands its role globally.

There are a few critical issues that this article does not address. First, I do not discuss North Korean sites associated with chemical or biological weapons. Instead, I focus on the challenges associated with eliminating North Korea's nuclear facilities given the extent of the program and its comparatively large destructive capacity. Second, I do not lay out the details of the scenarios that could lead to China's intervention. This has been done elsewhere, and the details are important only inasmuch as they shape the combat environment, nuclear use, or the conditions under which China would intervene—topics that I consider in the conclusion.23

The rest of this article proceeds as follows. In the first section, I derive six key indicators of intervention from the security studies literature. Then, in the second section I consider how current trends, including deteriorating DPRK-China relations, Beijing's expanding regional interests, and China's improved operational capabilities, could influence the likelihood and nature of Chinese intervention in a North Korean contingency. I make two arguments: (1) U.S. officials, strategists, and planners incorrectly assume that U.S. forces will be in a position to eliminate North Korea's nuclear facilities; and (2) the Chinese military is highly likely to take control of those facilities.24 In the third section, I evaluate Chinese WMD-C3D capabilities and conclude that although China's ability to secure North Korea's nuclear facilities is likely sufficient to prevent an accident, its current knowledge of the DPRK nuclear program and its weak verification procedures make proliferation beyond the peninsula a real threat. I argue in the fourth section that sound U.S. policy can mitigate these weaknesses, and therefore Chinese involvement carries more benefits than costs for U.S. operations on the peninsula. I conclude with recommendations for adjusting U.S. contingency plans to enhance cooperation with China and for ensuring that China's presence contributes to U.S. WMD-C3D goals.

Why States Intervene

Scholars of intrastate and interstate war have long sought to identify the factors most likely to determine whether an outside power will intervene directly in an ongoing conflict. The most recent research has focused on humanitarian intervention in civil wars, largely because after the collapse of the Soviet Union, civil wars became more frequent and therefore more likely than major power war. But with the rise of China and the resurgence of Russia, a return to theories of major power intervention is warranted.

In this section, I derive from the literature on great power intervention six factors, dispositional and situational, that influence whether a country will intervene in a conflict. The first predicator is the presence of an alliance commitment—a country is more likely to intervene in an ongoing conflict if its ally is party to that conflict.25 The second predicator is whether the potential intervener is a neighboring country. Specifically, if the potential intervener is experiencing large flows of inbound refugees as a result of the conflict or is merely concerned about the possibility, it is more likely to intervene.26 The third predicator of great power intervention is whether the countries fighting possess weapons of mass destruction—potential interveners may want to prevent their use or transfer to other actors.27

Economic considerations are the fourth predicator of whether a third-party country intervenes in a conflict. The costs of war discourage intervention, but there may be some material benefits that influence the calculus. For example, if a country is rich in lootable natural resources, this creates perverse incentives for third-party intervention.28

Geopolitical considerations are the fifth factor that could influence the cost-benefit analysis of a potential intervener. An intervener may want to shape the outcome of the war for strategic gain or to ensure that hostilities do not damage its vested interests in that country or in the region.29 Additionally, if an international rival has already picked a side in a war, a state is more likely to intervene on the side of an opposing party.30 If a country can protect its interests without engaging in direct military intervention—for example, by providing funding or supplies to one of the belligerents—then it may be less likely to intervene directly.31

The sixth predicator of intervention is the potential intervener's military capabilities, because if a state can intervene militarily in an ongoing conflict, it is more likely to do so.32 The resources needed for success, however, vary with the nature of the conflict itself; states are less likely to intervene in intense and prolonged conflicts associated with high costs and a low likelihood of success.33

In the next section, I evaluate these six predicators in the context of possible Chinese intervention in a Korea contingency.

Chinese Intervention in a Korea Contingency

In this section, I treat the six predictors for intervention derived in the previous section as independent variables. Based on information gathered from interviews and Chinese authoritative publications, I determine whether the value of each independent variable would predict a low, medium, or high probability of Chinese military intervention if conflict broke out on the Korean Peninsula. I also include a dynamic indicator of whether the impact of each independent variable on the intervention calculus is trending up or down or remaining stable. (See table 1 for a summary of the results.) Although these factors predict intervention of outside states more generally, concerns about refugees and nuclear security, geostrategic motivations, and improved military capabilities would all push China not only to intervene, but to seize control of North Korea's nuclear storage facilities, weapons, testing tunnels, and missile sites.

Table 1.

Predictors for Chinese Intervention on the Korean Peninsula

Independent VariableAlliance RelationshipRefugeesNuclear SecurityEconomic ConsiderationsGeopolitical ConsiderationsMilitary Capabilities
Likelihood of intervention medium high high low high medium 
Trend in importance of issue down stable up stable up up 
Independent VariableAlliance RelationshipRefugeesNuclear SecurityEconomic ConsiderationsGeopolitical ConsiderationsMilitary Capabilities
Likelihood of intervention medium high high low high medium 
Trend in importance of issue down stable up stable up up 

ALLIANCE RELATIONSHIP

As noted earlier, one of the main determinants of a state's decision to intervene in a conflict is its relationship with the belligerents. China has supported North Korea to varying degrees ever since it sent forces to fight against the U.S.-led United Nations coalition in the Korean War. In 1961, Beijing and Pyongyang signed the Sino-North Korean Mutual Aid and Cooperation Friendship Treaty, which was renewed most recently in 2001.

On the surface, it seems that this alliance relationship would predict a high likelihood that China would intervene if North Korea found itself at war with the United States.34 Over the past few years, however, relations between Beijing and Pyongyang have deteriorated to the point where Chinese strategists and even military officers were suggesting that China might not take North Korea's side in the event of a conflict on the peninsula. China has had a lot to be upset about. For example, since assuming power Kim has blatantly ignored China's demands to refrain from provocative activities, ordering eighty-six missile tests and four nuclear tests.35 Demonstrating a complete disregard for China's interests, Kim ordered all of the nuclear tests to be conducted at the Punggye-ri site, about 100 miles from the Chinese border, which caused significant consternation in Beijing given the leadership's concern about nuclear fallout.36 Moreover, the tests occurred during significant moments for Beijing, including Xi's May 2017 One Belt, One Road summit in Beijing and, a few months later, the BRICS (Brazil, Russia, India, China, and South Africa) summit in Xiamen. Xi may have felt personally disrespected by Kim's ordering of these tests, as it became obvious to the world that their timing was no coincidence.37

In this context, it is not surprising that Chinese leaders have been particularly vocal about their support for the peaceful reunification of North and South Korea sometime in the future, even if this entailed the demise of North Korea.38 State-sponsored documentaries about the Korean War and Chinese Communist Party official histories have sought distance from the original revolutionary narrative, suggesting in turn an official distancing from the alliance.39 Indeed, Beijing has commented that China would not come to North Korea's defense in a conflict with South Korea and the United States if North Korea was seen to have provoked the conflict, and polls conducted in China suggest that public opinion generally supports a weakened commitment to North Korea.40 Although not representing the majority viewpoint, scholars close to the Party have been allowed to voice their support for officially abandoning North Korea to better pursue a courtship of South Korea.41 But even though Chinese thinking about North Korea has become more flexible since the alliance was “forged in blood,” there still may be some conditions under which Beijing could come to North Korea's aid.42

Therefore, the PRC-DPRK alliance relationship creates a medium likelihood of Chinese intervention in a conflict involving North Korea, but has decreasing influence in Chinese decisionmaking.

REFUGEES

Given the proximity of North Korea and China, a conflict on the Korean Peninsula would raise significant concerns in Beijing about refugee flows, indicating a consistently high likelihood that China would intervene in such a contingency. As retired PLA Maj. Gen. Wang Haiyun wrote in a state-owned newspaper in 2017, “Once war breaks out, we should also consider setting up an international refugee camp in North Korean territory to prevent the influx of North Korean refugees.”43

Recognizing this concern, China has plans to seal its border with North Korea and to conduct border control operations, which could include moving Chinese forces a minimum of 50 kilometers into North Korea—though the Central Politburo Standing Committee would ultimately decide whether to execute such a plan.44 An authoritative Chinese military publication notes that the best option would be to establish refugee camps within North Korea, but China could also set up refugee camps and establish controlled areas to separate North Korean civilian, military, and political personnel in various locations along the border. Ideally, China could create three buffer zones: (1) a blockade to control major ports throughout North Korea to prevent the outflow of North Korean refugees or fleeing North Korean military personnel, (2) a zone to intercept and search the refugees (ostensibly to ensure they are not transporting weapons or nuclear materials), and (3) a checkpoint 100 kilometers into Chinese territory to intercept refugees who manage to penetrate the border.45 China would then need to establish regulations on North Korean repatriation. For refugees allowed to stay in China, Beijing would need to set up education programs to familiarize them with Chinese culture and to equip them with vocational skills.46

Even if Chinese contingency plans are limited to dealing with the refugee issue, as Barry Posen notes, “those contemplating the use of military force for humanitarian purposes should think of themselves as planning a major foreign policy initiative that will likely end in war.”47 Without effective control measures, terrorists, separatists, extremists, or hostile foreign forces and spies could enter along with civilians.48

Because China could best manage and contain a refugee crisis if it created a buffer zone within North Korea, and because the flow of people and potentially dangerous material would have a direct impact on Chinese national security, it is highly likely that China would intervene in a North Korean conflict. But because the seriousness of the refugee issue has not changed in decades, its impact on the likelihood of intervention is likely to remain stable.

NUCLEAR SECURITY

Even if China confined its goals to dealing with North Korean refugees, a number of North Korean nuclear facilities would likely be within the Chinese-controlled buffer zone. Of the most important known North Korean nuclear and missile sites, around 44 percent of the former and 22 percent of the latter are located 50 kilometers or less from North Korea's border with China. An advance of only 100 kilometers from the Chinese border would give the PLA control of almost all of North Korea's priority nuclear sites and a majority of its priority missile sites.49 Chinese military officers, in fact, have stated that contingency plans are in place for a mission to secure DPRK nuclear weapons and fissile material.50

Increasingly, however, security concerns are driving Chinese leaders’ desire to seize control of critical North Korean nuclear-related sites in the event of a conflict on the peninsula.51 In the words of a well-known Chinese expert on North Korea, “Stepping back, if a Korean nuclear bomb explodes, who'll be the victim of the nuclear leakage and fallout? That would be China and South Korea. Japan is separated by a sea, and the United States is separated by the Pacific Ocean.”52 The presence of Chinese forces at North Korean nuclear sites would reduce the likelihood of cross-border contamination in two ways: (1) by deterring the United States, Japan, or South Korea from striking these sites; and (2) by preventing Pyongyang's use of nuclear weapons, a nuclear accident, or sabotage.53

In support of these objectives, China announced in 2016 that it would create a force of both military and civilian personnel dedicated to responding to nuclear emergencies, including nuclear accidents in foreign countries.54 The Nuclear Emergency Response Center was apparently set up to organize this force to conduct operations such as coordination and technical support; emergency rescue; emergency monitoring and radio protection; decontamination; and medical rescue.55

In sum, protecting China from nuclear fallout or use is an acute concern for Beijing, and securing North Korean nuclear facilities reduces the likelihood of a nuclear accident. Therefore, nuclear security concerns create an increasingly high likelihood of Chinese intervention in a North Korean conflict.

ECONOMIC CONSIDERATIONS

For any state, there are financial and human costs associated with engaging in a military conflict and dealing with its aftermath. In a scenario involving reunification on the Korean Peninsula, South Korea could be expected to dedicate at least 1.5 percent of its gross domestic product per year to aid North Korea for at least five years.56 China could be pressured to provide aid for the reunification effort, especially if it were directly involved in the conflict that preceded reunification. After reunification, China could lose the economic benefits provided by treaties with North Korea, such as access to shipping ports and the right to extract minerals and raw materials on favorable terms.57

At first glance, then, economic considerations would seem to discourage Chinese intervention in a contingency on the peninsula, but these are unlikely to be prohibitively high, for two reasons. First, while operating on the peninsula, China would have short logistics lines and an ability to rely on assets within its own territory. Second, Chinese troops would face less resistance from North Korean troops, because Kim would concentrate his forces southward to deal with the ROK and the United States.58

Additionally, Chinese intervention could have economic benefits. Early intervention could quickly stabilize the situation in North Korea, preventing collapse, or in a war scenario, ensure that the conflict is short and limited. This could minimize the disruption to South Korean trade and foreign direct investment in China. Such disruption would be problematic given that South Korea is China's third-largest trading partner and invests $124 billion in its economy.59

Reunification of the Korean Peninsula could provide certain economic benefits to China that could outweigh the short-term costs of military intervention.60 Many Chinese experts expect that trade volumes would increase dramatically at the regional, national, and even international levels after reunification.61 More than a decade ago, even before Chinese scholars and elites had begun to discuss the prospect of reunification publicly, Ministry of Finance and Commerce officials commented in meetings with the author that reunification would be a positive development for the Chinese economy.62 This would be true, however, only if China were involved militarily in the contingency to ensure reunification on terms favorable to Beijing. Then China could begin, for example, to transport goods overland through North Korea, decreasing costs and allowing South Korea to take advantage of low-cost labor and abundant resources in the northeast part of the country.63 In addition, China could gain access to more Korean ports, potentially reducing congestion in its own ports.64

In sum, a conflict on the Korean Peninsula would entail economic costs and benefits for China, but none so great as to be the determining factor in China's decisionmaking calculus. Moreover, China's economic calculus has not evolved significantly in the past two decades. Therefore, consideration of economic factors alone would predict a low likelihood of direct Chinese intervention, a level of impact likely to remain stable in the future.

GEOPOLITICAL CONSIDERATIONS

In a conflict on the Korean Peninsula, geopolitical factors would contribute significantly to the likelihood of the PLA seizing North Korean territory and nuclear facilities in an effort to realize its national security and regional power aspirations in the aftermath of hostilities.65 One factor motivating such a move is the concern, expressed by several Chinese interviewees, that allowing the United States to secure DPRK nuclear facilities would be akin to granting South Korea ownership over North Korea's nuclear weapons. Some interviewees stated as a reason for this concern a belief that the United States supports a nuclear South or reunified Korea, but cannot provide Seoul directly with nuclear weapons or needed technologies because of international pressure; delaying the elimination of the North Korean program would provide a useful loophole. A more realistic belief, however, is that South Korea would go against U.S. wishes and take the weapons.66 Although perhaps far-fetched, this concern may be a reaction to the ongoing debate in South Korea about the benefits of nuclear weapons.67 Ironically, China prefers a denuclearized Korean Peninsula and feels that it can guarantee this outcome only by eliminating the DPRK nuclear program.68

Second, China fears that a denuclearized Korea under U.S. influence would pose a threat to stability along China's northeastern border and limit China's quest for regional power.69 These geopolitical considerations are becoming more salient, largely as a result of China's growing confidence and increased focus under Xi Jinping on the rejuvenation of the Chinese nation and the return of China to what it considers its rightful place as the regional hegemon. As one PLA officer articulated when asked if China would intervene in a conflict on the peninsula, “Why should the United States be there but not us?” The future of Korea, and of U.S. forces on the peninsula, could tip the balance of power and influence China's behavior.

In sum, the last thing China wants in the wake of a conflict on the peninsula is to deal with North Korean instability, or even to absorb the costs of conflict, only to be left with a postwar outcome that strengthens the U.S. role in the region. For these reasons, geopolitical concerns create a high likelihood of Chinese intervention in a conflict on the peninsula. China would need to control territory if it were to have a seat at the wartime negotiating table. As China seeks to increase its regional influence, the influence of geopolitical factors on a decision to intervene will only increase.

MILITARY CAPABILITIES

Much has been written about recent improvements in China's military capabilities, including its ground forces and strategic forces, that would make China better able to intervene militarily in a North Korean contingency.70 In the event of Chinese military intervention on the Korean Peninsula, all operations would be carried out by a ground force directed by the newly formed Northern Theater Command, headquartered in Jinan.71 As part of the greatest reorganization of the Chinese military since the 1950s, the number of PLA armies was cut from eighteen to thirteen; divisions were eliminated; new combined arms formations were created; many units moved to new locations; smaller units joined existing brigades; and the missions and composition of forces at each level were transformed.

All this movement and change creates a degree of uncertainty for China military scholars about the exact components that would be relevant to a North Korean contingency. Three group armies, however, remain in the Northern Theater Command (the 78th, 79th, and 80th), each with 30,000 to 50,000 troops and its own Army Aviation Brigade consisting of about 1,000 individuals and a Special Operations Forces (SOF) Brigade of about 2,000 individuals. Both would likely play key roles in any WMD-C3D mission.72 The Aviation Brigades have the transport (Mi-17, Z-8, Z-9) and attack helicopters (Z-10, Z-19) needed for close air support and lift capabilities into North Korea.73 The Z-10 brigades conducted a live-fire drill in June 2017, probably to practice low-altitude penetration techniques that would be crucial for the insertion of forces into select nuclear facilities in a conflict.74 In the event of a conflict on the peninsula, Army Aviation Brigades and SOF Brigades from Central Theater Command could be brought in, as could airborne units assigned to the PLA Air Force.75 China could also enter North Korea by sea, an approach suggested by the recent addition of Shandong, a coastal province, to the Northern Theater Command.76

China may, in fact, be actively preparing for a Korea contingency. Since 2015, it has conducted a majority of its naval drills in the Bohai and Yellow Seas off the coast of North Korea and Japan. At least three of the major exercises have been carried out in the waters close to North Korea, and China's Strategic Rocket Force practiced shooting down incoming missiles over these waters only days after North Korea conducted its sixth nuclear test, in September 2017.77 A Chinese naval expert commented that such exercises show that “China is prepared and able to stop any power that threatens stability in the region.”78 A Shanghai-based military expert added that China “is now under growing threat from the Korean Peninsula, so the Chinese navy must demonstrate and improve its defense and combat abilities.”79 Engaging militarily on the Korean Peninsula would also allow China to test its new capabilities against a less advanced North Korean adversary. At the same time, it would not face the kind of domestic political pressure that would be associated with a Taiwan, East China Sea, or South China Sea campaign.80

In sum, China's improving, but untested, military capabilities suggest a medium likelihood of Chinese intervention in a conflict on the Korean Peninsula. But as recent institutional reforms, improved readiness, and more realistic training continue to enhance the PLA's mobility and ability to conduct joint operations, China's willingness to intervene militarily will increase in tandem.81

China and the WMD-C3D Mission

In a conflagration on the Korean Peninsula, alliance politics, refugee and nuclear security concerns, economic considerations, geopolitical considerations, and military capabilities could all play a role in Chinese decisionmaking about whether to intervene. Increasingly, however, China's leaders are weighing the nuclear security concerns, geopolitical implications, and likelihood of success shaped by military capabilities in the event not only of a war, but also of a regime collapse in Pyongyang. Given that these three factors on aggregate predict a high and increasing likelihood of Chinese intervention, I posit that China would probably undertake an extensive military intervention if a major conflict broke out on the Korean Peninsula. Recent Chinese statements and military training exercises also point to heightened preparations for intervention. After the fifth DPRK nuclear test, for example, a senior Chinese military adviser called on China to adjust its force deployment on the northeast border to better prepare for war on the peninsula.82 In late April 2017, the PLA conducted live-fire drills near the China-North Korean border, and there were rumors of a Chinese troop buildup close to North Korea—though the Chinese Ministry of Defense denied such non-routine preparations.83 Although the nature and degree of Chinese intervention would be situationally dependent, to be best prepared, U.S. planners should assume that Chinese forces would be more likely than not to intervene.

If China did intervene, would it have the capabilities to conduct a successful WMD-C3D mission in North Korea? The Chinese military has no doubt prepared and planned for such a contingency; however, this article represents the first attempt to assess whether China could leverage its experience as a nuclear power to conduct WMD-C3D.84 The first challenge would be to secure North Korea's nuclear facilities, nearly all of which are located in the northern 100 kilometers of the country.85 The PLA would likely reach these facilities sooner than any other forces, thanks to China's geographical proximity to North Korea, the location of its troops, and the possibility that North Korean troops would exhibit relatively low resistance to Chinese forces.86 China might also enjoy early warning, allowing for advanced preparation, because its shared border with the DPRK provides China with unique opportunities to collect intelligence.87 China has a number of radar and signals intelligence stations near the border that could either detect launches after delivery vehicles break the horizon or intercept launch site communications. Also, North Korea likely uses fiber optics, satellite communication, and high frequency radio for its diplomatic communications. Although the United States could pick up satellite communication or high frequency radio transmissions, China has unique access to North Korea's fiber optic communications, as two of the three cables linking North Korea to the outside world run through China (i.e., through the cities of Hunchun and Dandong).88

Moreover, Chinese reporting suggests that the border is under twenty-four-hour electronic surveillance, and the PLA works with local and border authorities to ensure strict management and control measures, early warning, and consequently a swift response to any crisis.89 According to a recent RAND study, “Due to its proximity, absence of significant military barriers, existence of more rail lines and roads into China than into South Korea, and the sheer size of its military, China can essentially penetrate as far into North Korea as it chooses.”90 In comparison, U.S. forces seeking to conduct stability operations would move much more slowly and with more difficulty.91

Once in the vicinity of the sites related to North Korea's nuclear weapons program, the PLA would need to identify and characterize them before securing them. Chinese interviewees highlight limited Chinese intelligence on the location and nature of the DPRK nuclear program as a major limitation to WMD-C3D operations. The common viewpoint among them is that U.S. collection capabilities are more expansive and sophisticated than China's.92 Although China's surveillance capabilities are not publicly available, the alleged purchase by Germany of DPRK intelligence from China and Zhou Yongkang, a former member of the Politburo Standing Committee accused of selling DPRK nuclear secrets to foreign entities, implies that Beijing may possess such capabilities.93

Once the PLA identified North Korea's most important nuclear sites (those that store the most material and have the least redundancy in capability), it would move to secure the suspected sites, identify the nuclear threats or hazards at each site, render safe any weapons or materials that posed an immediate threat, prevent their unauthorized movement, and preempt U.S. action.94 The PLA initially might use elements of the two Army Aviation and two SOF Brigades in the region, augmented by Army Aviation and SOF Brigades from the Central Theater Command around Beijing, to secure and hold other key objectives until they could be relieved by brigades moving overland. In the meantime, the border would likely be secured by the People's Armed Police, which number approximately 50,000 in the Northeast provinces.95

The work of identifying and minimizing nuclear dangers would be led by the PLA's sanfang units, which were created to address nuclear, biological, and chemical threats, although units from across all of the Chinese military services have reportedly been trained to deal with nuclear contingencies.96 After securing North Korea's WMD sites, the PLA would invite external technical experts, likely from the Chinese Engineering and Physics Institute, the China Institute of Radiation Protection, and the China Aerospace Science and Technology Corporation, to support the mission.97 Additional expertise on missile technology and nuclear weapons would be contributed by the Strategic Rocket Force.98

Unfortunately, few Chinese writings explicitly discuss the WMD-C3D mission in detail as it pertains to North Korea. It is possible, however, to glean additional insights from recent efforts in China's civilian nuclear emergency realm, because some aspects—such as the securing of sites, accounting and verification of what is present and missing from sites, safe transport, and civilian-military coordination mechanisms—are similar to those of the WMD-C3D mission. Establishing civilian military coordination mechanisms has been a recent focus of the Chinese government. In January 2016, it released a white paper on nuclear emergency preparedness laying out regulations on the “organizational system, command and coordination mechanism, emergency response classification, post-accident restoration actions, and emergency preparation and safeguard measures related to nuclear emergency preparation and response actions.”99 In support of these efforts, China set up six teams in May 2016, each of which consists of a command coordination and technical support unit, assault and rescue unit, engineering rescue unit, emergency monitoring and radiation protection unit, decontamination unit, and medical rescue unit. National Nuclear Emergency Support Centers were established in July of the same year to provide technical support in radiation monitoring and prevention, aviation monitoring, medical rescue, marine radiation monitoring, and meteorological monitoring and forecasting.100 In a nuclear contingency, the military would take the lead, and according to one media source, there are already 50,000 troops dedicated to the mission.101

These new initiatives to enhance China's nuclear emergency preparedness reveal three important takeaways for a North Korean contingency. First, the Chinese official white paper explicitly states that the civil-military command and coordination mechanism can be used beyond China's borders. Second, because the National Nuclear Emergency Support Centers have been tested and perfected for contingencies, China would be able to quickly set up the command and control mechanisms needed for a WMD-C3D mission. Third, many of the skills exercised in the civilian sphere that meet International Atomic Energy Agency (IAEA) standards are useful in the military sphere—China is capable of safely transporting nuclear material, disposing of waste, and establishing an effective accounting and control system.102 These Chinese civilian capabilities suggest that China would be relatively effective at accounting for and controlling the materials at all North Korean nuclear sites and preventing their proliferation during the complex process of transporting materials to more suitable sites for evaluation and destruction if necessary. Nevertheless, there is still room for improvement; for example, one Chinese source notes that security around transportation and tracking activities should be increased to prevent third parties (e.g., terrorists) from seizing nuclear material.103

In terms of challenges, Chinese writings suggest, first, that although Chinese troops would help secure North Korea's nuclear facilities, China may not have enough experts to characterize the sites and render them safe.104 Second, without the proper intelligence, Chinese forces would not know what was supposed to be present at a given location and, therefore, would be unable to verify whether any nuclear weapons or related materials—such as plutonium, which is small and easy to hide—were missing. In particular, they might have difficulty detecting the movement of small amounts of such materials.105 Third, although China could secure these facilities with a high degree of confidence, its standard of nonproliferation may be lower than that of the United States. Beijing may not be willing to expend the resources to prevent weapons, dangerous materials, and those with nuclear expertise from leaving North Korea, but may instead focus simply on preventing them from entering China.106 Proliferation could then happen accidentally, or purposefully given the financial incentives created through the demand by state and nonstate actors alike for such components or personnel.

Assessing China's ability to dismantle nuclear weapons is more difficult than assessing its ability to identify and secure relevant sites. On one hand, China is a nuclear power with experience dismantling its own outdated systems. Also, according to one Chinese scientist, North Korean weapons technology is fairly simple, with configurations similar to those of Chinese weapons.107 U.S. interviewees have stated, however, that the more primitive the weapon, the harder it is to dismantle safely, because safeguards may not be in place. In addition, scientists need the exact weapon designs and access to the weapons’ engineers to ensure that dismantlement can be undertaken without incident.108

In conclusion, China has the ability to conduct most aspects of the WMD-C3D mission, though support from the United States and the international community could improve the effectiveness of its efforts. In the next section, I lay out in more detail the operational benefits of Chinese intervention in a North Korean contingency and offer recommendations for U.S. policy to mitigate some of the weaknesses in China's WMD-C3D capabilities.

The Operational Benefits of Chinese Intervention

Much has been written about the potential implications and challenges for the United States if the North Korean regime were to collapse.109 If conflict broke out on the peninsula, the United States would have a number of strategic objectives with respect to North Korea's nuclear weapons. The current prioritization of risk mitigation is as follows: (1) prevent North Korean countervalue strikes against the United States, Japan, and South Korea; (2) prevent nuclear use against U.S. and allied forces; (3) prevent nuclear sabotage in North Korea that could lead to injury as a result of an explosion or contamination from radioactive materials; (4) render safe and secure the nuclear weapons and material on the peninsula to prevent theft, smuggling, and broader proliferation; and (5) eliminate all nuclear weapons and related facilities from the peninsula.110 The WMD-C3D mission is critical because if done successfully and quickly, it can contribute to all these objectives. From a capabilities standpoint, however, WMD-C3D is a tactical-level mission that focuses mainly on the fourth and fifth tasks.

U.S. policymakers and military planners have long argued that Chinese involvement in a North Korean military contingency would be detrimental to U.S. interests. They give three main reasons for the undesirability of Chinese involvement.111 First, many believe that China would intervene to protect and prop up North Korea, including securing nuclear weapons for the regime in Pyongyang, which would run counter to the U.S. goal of denuclearizing the peninsula. As this article demonstrates, however, China's position on North Korea has evolved significantly in recent years, and Chinese forces are more likely to oppose North Korean forces than to fight alongside them.112

Second, bureaucratic inertia inclines some U.S. military leaders to regard third-party intervention as a threat to the mission because it may prevent them from conducting the WMD-C3D mission as planned. If the United States insists on securing and destroying North Korean nuclear facilities itself, then China's presence does endanger that mission. For example, Chinese presence around critical nuclear facilities would complicate any U.S./ROK plans to secure and destroy those facilities themselves, to include conducting standoff attacks.113 Moreover, if Chinese troops and U.S. troops rushed to the same sites, the risk of unintentional clashes would increase dramatically. In short, if the United States fails to adjust its thinking and insists on pushing Chinese troops out of the North Korean nuclear sites, the result could be a war between the United States and China.

Third, the operational benefits of Chinese involvement in a North Korean contingency would come with a strategic trade-off for the United States—that is, China would use its presence in North Korea and its possession of the critical nuclear sites, weapons, and material to ensure reunification on terms favorable to Beijing. Among other things, this would likely include a demand that U.S. forces withdraw from the peninsula. If the United States refused, Beijing might block reunification efforts and choose instead to insert a pro-Beijing regime in Pyongyang.114

In contrast to the above conventional wisdom, I argue that Chinese military involvement in a Korea contingency would benefit U.S. WMD-C3D objectives at almost every stage of the mission. For example, the United States’ plan is to first attempt to identify, isolate, and secure key sites, including nuclear research, production, storage, and delivery facilities; search and clear them of WMD; and do so possibly while sustaining major war operations.115 Studies show that the large number of WMD sites in North Korea would require massive combat forces to support the WMD-C3D mission, around 188,000 troops, though estimates vary greatly, depending on whether U.S. troops faced a hostile environment.116 With only 28,500 U.S. troops currently in South Korea, the U.S. military would have to fly in troops from the United States and Japan over several months. If resistance were light, the United States could drop airborne forces into the most worrisome sites, but it would take weeks for ground forces to flow in through the ports and across the border from South Korea.117 The mission would also take troops away from broader combat and stabilization operations for unspecified periods of time.118 Granted, under the United Nations Command, military personnel from South Korea and from the sending states would contribute greatly to the overall campaign. But given Nonproliferation Treaty limitations, South Korean troops could not take responsibility for the WMD-C3D mission. China, however, has both the authority to deal with nuclear materials (as a recognized nuclear state in the Treaty) and the necessary manpower, and it could take on this mission while freeing up U.S. troops to focus on warfighting and stabilization efforts. Moreover, because Chinese forces have the geographic and logistical advantage, they would likely reach these facilities sooner. Nuclear weapons in the hands of China would mean that North Korea could not detonate them, thereby avoiding a nuclear war.

China could also contribute to the goal of nonproliferation. In addition to shutting down the northern border to contain the flow of people and dangerous material, the Chinese military could conduct surveillance; secure high-priority WMD targets; and sweep the country to secure, inspect, and identify North Korea's nuclear weapons facilities.119 Lastly, after a nuclear site had been secured and its contents identified, the United States would want to dismantle the facility and render safe any weapons or nuclear material found there. Admittedly, this part of the mission would be difficult to concede to China, as its dismantle-and-destroy capabilities are a key weakness. Chinese weaknesses in this area, however, may not detract from the overall success of the WMD-C3D mission, for two reasons. First, China may decide not to dismantle the weapons—it could take them to China for study and indefinite storage. This option is not discussed in great detail in the United States, primarily because U.S. policy assumes that destruction will always take place within the possessing country.120 Second, Chinese scientists have indicated in interviews with the author a willingness to share the burden of dismantlement with international agencies such as the IAEA.121

In short, encouraging China to conduct the WMD-C3D mission, or facilitating its ability to do so, may be beneficial for the U.S./ROK war effort and regional security. Chinese control would lower the likelihood of nuclear use on the peninsula in the short term and, potentially, reduce the economic and military burden to the United States of conducting WMD-C3D in the long term. Additionally, U.S. acceptance of China's WMD-C3D role would avoid unnecessary clashes between Chinese and U.S. troops that could escalate to full-blown war.

Conclusion

Given China's increasing concerns about nuclear security, desire to control refugee flows into China, expanding and improved military capabilities, and geopolitical competition with the United States, China is likely to intervene directly and militarily if war breaks out on the Korean Peninsula. Although China's potential involvement has traditionally been seen as a threat to any U.S. mission under similar circumstances, I argue that the benefits of the Chinese military's involvement outweigh the costs. The primary objective in a conflict scenario is to prevent the use of nuclear weapons by North Korea; China has the manpower and capabilities to identify and secure North Korean nuclear facilities effectively and more quickly than the United States. Moreover, in areas of the WMD-C3D mission where China is still potentially weak, such as nonproliferation and the dismantling of nuclear weapons, Beijing has shown a willingness to work with the IAEA and potentially even the United States to meet U.S. standards of success in these areas. Chinese involvement, however, comes at a geopolitical price in that Beijing will demand greater influence on the peninsula at the expense of the United States and its alliance with South Korea.

This research generates a number of recommendations for U.S. policy.122 First, planning to conduct a unilateral U.S. WMD-C3D mission in North Korea may not be a viable option. Evidence suggests that if conflict broke out on the Korean Peninsula, China would take control of some, if not all, of North Korea's major nuclear facilities. China's interests are no longer limited to securing its border to prevent an influx of refugees.123 The United States may not get a vote in whether China is involved, and therefore needs to embrace the benefits of Chinese intervention and change its approach to mitigate the associated challenges.

There are a number of initiatives the United States can take before any crisis to defuse the risks associated with potential Chinese involvement. A rush of U.S. and Chinese forces to North Korean nuclear sites would introduce a high risk of miscalculation and undermine escalation management. This research suggests there may be no need to rush; the benefits of Chinese control over DPRK nuclear facilities, in terms of a reduced likelihood of nuclear use, may outweigh the costs, at least operationally. This would only be the case, however, if the PLA did not overlook sites that the United States deemed important. To prevent the PLA from overlooking any sites, the United States might consider sharing intelligence with China about certain facilities and what the U.S. intelligence community predicts will be there. Currently, there are no established channels through which such intelligence could be shared, and figuring out how to do so while minimizing operational risk would take significant bureaucratic effort.

Second, the United States might consider steps to address China's lesser capability and interest in the dismantlement and destruction components of the WMD-C3D mission. For the United States, these final steps are so critical that China's shortcomings in this area alone may be reason enough to rush to secure the facilities. To avoid that necessity, the United States might consider combined training or exercises to enhance Chinese dismantlement and destruction capabilities. Moreover, as China's global role expands, enhanced WMD-C3D capabilities may encourage Beijing to contribute more actively to nuclear security missions elsewhere, such as in Syria or Iran. If the core issue is Beijing's reluctance to include a dismantle-and-destroy component in its mission, Washington could communicate a willingness to provide financial support or expertise under the umbrella of international institutions, which Chinese interlocutors have suggested might be welcome. Additionally, if China is unwilling to furnish the resources to secure its borders with North Korea and conduct maritime and aerial interdiction operations to prevent the movement out of North Korea of people and materials of concern to the degree desired by the United States, U.S. and South Korean combined forces could take on that aspect of the nonproliferation mission.

Achieving the objectives described above would require massive amounts of U.S.-China coordination. For political reasons, Beijing may not want to participate—especially in the absence of conflict on the peninsula. In this case, the United States would need to consider the benefits of unilateral transparency and communication. Also, any discussion about DPRK disarmament should be done through a new, separate channel, so as to avoid the sensitivities associated with arms control talks between the United States and China.

If China continues to be reluctant to coordinate planning efforts, the United States might consider contributing to China's nuclear emergency training through less politically sensitive means, such as civilian training or technical exchanges.124 The United States and China have already made great strides in nuclear security cooperation. Bilateral discussions on nuclear security were held for the first time on February 20, 2016, and both sides have agreed to continue these discussions on an annual basis. The two countries continue to engage in a number of technical areas, including the opening of the Nuclear Security Center of Excellence in China, which serves as a regional training center on best practices in nuclear safety.125 Cooperation in WMD-C3D could also be structured so as not to require visits to each other's nuclear laboratories and sites, which would be sensitive. Or the United States could shape some of the international exercises that China participates in and support China's expanded involvement.126 The effort to counter nuclear smuggling offers another promising channel for cooperation; China and the United States have already indicated their willingness to participate in this effort.127 It is also possible that U.S. experts and officials could observe China's national-level nuclear emergency joint exercises, such as the Shendun exercises.128

A decade after its first nuclear test, North Korea is still “the most volatile and dangerous threat” facing the United States and its treaty allies in Northeast Asia.129 Chinese military capabilities and their potential application in contingencies have greatly expanded since then, with China embracing new missions that seemed unthinkable just a few years ago.130 The way the United States manages its relations with China, both during and before a crisis on the Korean Peninsula, needs to evolve in tandem. Failure by the United States to embrace new thinking and new approaches could affect the prospects for peace on the peninsula, U.S.-China relations more broadly, and the future of global nonproliferation regimes. By testing and potentially transforming U.S.-China relations, any crisis on the peninsula will reverberate far beyond the two Koreas.

Acknowledgments

The author would like to thank the anonymous reviewers as well as those who provided feedback at research seminars at Stanford University, the Naval Postgraduate School, Harvard University, Wellesley College, and the University of Maryland. She is also grateful to John Chen, Annie Kowalewski, Danni Song, Yilin Sun, and Christian Verhulst for their expert research assistance.

Notes

1. 

Peter Baker and Choe Sang-Hun, “Trump Threatens ‘Fire and Fury’ against North Korea If It Endangers U.S.,” New York Times, August 8, 2017; and Choe Sang-Hun, “Kim's Rejoinder to Trump's Rocket Man: ‘Mentally Deranged U.S. Dotard,'” New York Times, September 21, 2017.

2. 

“North Korean Nuclear and Missile Tests in 2017,” South China Morning Post, November 29, 2017.

3. 

Mark Landler, “The Trump-Kim Summit Was Unprecedented, but the Statement Was Vague,” New York Times, June 12, 2018; and “The Trump-Kim Statement: Read the Full Text,” New York Times, June 12, 2018.

4. 

Choe Sang-Hun, “North Korea's Big Moment Is Upended by Trump,” New York Times, May 24, 2018; Choe Sang-Hun, “North Korea Starts Dismantling Key Missile Facilities, Report Says,” New York Times, July 23, 2018; Ellen Nakashima and Joby Warrick, “North Korea Working to Conceal Key Aspects of Its Program, U.S. Officials Say,” Washington Post, June 30, 2018; and Julian E. Barnes and Eric Schmitt, “Trump Promotes Diplomatic Gains, but North Korea Continues Building Missiles,” New York Times, July 31, 2018.

5. 

Gardiner Harris and Choe Sang-Hun, “North Korea Criticizes ‘Gangster-Like’ U.S. Attitude after Talks with Mike Pompeo,” New York Times, July 7, 2018.

6. 

Choe Sang-Hun, “U.S. Reneging on Deal, North Korean Envoy Says,” New York Times, August 5, 2018.

7. 

Orville Schell and Susan L. Shirk, US Policy toward China: Recommendations for a New Administration (New York: Center on U.S.-China Relations, Asia Society, 2017); and U.S. Department of State, “Secretary of State Rex Tillerson and Secretary of Defense Jim Mattis at a Joint Press Availability” (Washington, D.C.: U.S. Department of State, June 21, 2017), https://www.state.gov/secretary/20172018tillerson/remarks/2017/06/272103.htm.

8. 

U.S. Department of State, “Secretary of State Rex Tillerson and Secretary of Defense Jim Mattis at a Joint Press Availability.”

9. 

David E. Sanger and Choe Sang-Hun, “North Korean Nuclear Test Draws U.S. Warning of ‘Massive Military Response,'” New York Times, September 2, 2017.

10. 

For assessments of the contingencies, see Bryan Port, “North Korean Collapse or Korean Reunification: The Importance of Preparation over Prediction,” Military Review, Vol. 96, No. 5 (September-October 2016), pp. 8–19, https://www.armyupress.army.mil/Portals/7/military-review/Archives/English/MilitaryReview_20161031_art001.pdf; Paul B. Stares and Joel S. Wit, “Preparing for Sudden Change in North Korea,” Council Special Report, No. 42 (New York: Council on Foreign Relations, January 2009); Michael O'Hanlon, “North Korea Collapse Scenarios,” Brookings, June 9, 2009, https://www.brookings.edu/opinions/north-korea-collapse-scenarios/; and Center for U.S. Korea Policy, “North Korea Contingency Planning and U.S.-ROK Cooperation” (New York: Asia Foundation, September 2009). For a South Korean perspective, see Jung-hyun Cho, Dong-ho Han, and Ji-yong Lee, “North Korean Contingency and Resolving Conflicts among Regional States,” North Korean Review, Vol. 8, No. 1 (Spring 2012), pp. 37–52, doi:10.3172/NKR.8.1.37.

11. 

Bruce W. Bennett and Jennifer Lind, “The Collapse of North Korea: Military Missions and Requirements,” International Security, Vol. 36, No. 2 (Fall 2011), pp. 84–119, doi:10.1162/ISEC_a_00057.

12. 

Timothy M. Bonds et al., Strategy-Policy Mismatch: How the U.S. Army Can Help Close Gaps in Countering Weapons of Mass Destruction (Santa Monica, Calif.: RAND Corporation, 2014), p. 103. For more on these mission sets, see Bennett and Lind, “The Collapse of North Korea.”

13. 

Under Secretary of Defense for Policy, U.S. Department of Defense, “Department of Defense (DoD) Combating Weapons of Mass Destruction (WMD) Policy,” Directive 2060.02 (Washington, D.C.: U.S. Department of Defense, April 19, 2007), p. 9, https://www.hsdl.org/?abstract&did=779714. The updated guidance does not outline military “mission areas,” but instead issues broader guidance to “support military-force planning and doctrine to organize, train, exercise, and equip the Military Services to counter WMD; and prepare appropriate plans to address the defense-related aspects of CWMD.” Under Secretary of Defense for Policy, U.S. Department of Defense, “DoD Combating Weapons of Mass Destruction (WMD) Policy,” Directive 2060.02 (Washington, D.C.: U.S. Department of Defense, January 27, 2017), p. 3, http://www.esd.whs.mil/Portals/54/Documents/DD/issuances/dodd/206002_dodd_2017.pdf.

14. 

U.S. Department of Defense, “Department of Defense Strategy for Countering Weapons of Mass Destruction” (Washington, D.C.: U.S. Department of Defense, June 2014), p. 1, http://archive.defense.gov/pubs/DoD_Strategy_for_Countering_Weapons_of_Mass_Destruction_dated_June_2014.pdf.

15. 

Many studies evaluate the likelihood of Chinese intervention without evaluating how China's presence could affect the WMD-C3D mission. See, for example, Bruce Bennett, Preparing for thePossibility of a North Korean Collapse (Santa Monica, Calif.: RAND Corporation, 2013). Bennett and Lind equate intervention with the conduct of WMD-C3D; in other words, if China decided to intervene, it would help to dismantle the North Korean nuclear program. See Bennett and Lind, “The Collapse of North Korea.” This expectation may be true, but it requires deeper analysis. For another report that includes an assessment of how the potential contribution of coalition partners, including China, would improve the prospects of mission success, see Bonds et al., Strategy-Policy Mismatch, pp. 46–47.

16. 

During the Barack Obama administration, a shift in terminology occurred from WMD-E to CWMD (counter-WMD). The latter term covers activities designed to control, defeat, disable, and dispose of WMD, a change likely made because of the term's post-Iraq War connotations. I refer to this mission throughout the article as the WMD-C3D mission. Originally, CWMD referred to “combating” WMD, but the change was made to “countering” to acknowledge that significant nonmilitary tools should be brought to bear. Given that the United States would likely be involved in combat operations while attempting to control, defeat, disable, and dispose of North Korean nuclear weapons, I believe the characterization is still apt.

17. 

Jia Qingguo, “Time to Prepare for the Worst in North Korea,” East Asia Forum, September 11, 2017, http://www.eastasiaforum.org/2017/09/11/time-to-prepare-for-the-worst-in-north-korea/. Zhu Zhihua, vice president of Zhejiang Institute of Contemporary International Studies, wrote a critique of Jia's piece, arguing that Jia catered too much to U.S. preferences and ignored the role of the United States in bringing about this nuclear crisis. Even so, Zhu also recommended that China “actively prepare for military struggle” on the Korean Peninsula. See Zhu, “Ping Jia Qingguo zai Chaohe weiji shang de yipaihuyan” (Comment on Jia Qingguo's nonsense on North Korea nuclear crisis), Zhongmei Yinxiang, September 12, 2017, http://m.uscnpm.com/wap/article.aspx?d=98&id=14098.

18. 

Jia, “Time to Prepare for the Worst in North Korea.”

19. 

For more on these organizations and their likely involvement, see Robert J. Peters and W. Seth Carus, “Interagency and Intra-Agency Aspects of U.S. Elimination Activities,” Nonproliferation Review, Vol. 23, Nos. 1–2 (March 2016), p. 102, doi:10.1080/10736700.2016.1181823.

20. 

The need to fight on two fronts could also weaken North Korean resistance against U.S. and South Korean forces.

21. 

Current estimates suggest that there are thirty-nine nuclear sites and forty-nine missile sites. Bonds et al., Strategy-Policy Mismatch, pp. 50–51. North Korea's estimated ten to twelve nuclear weapons and stockpile of 75 to 320 kilograms of highly enriched uranium could be at these known sites or in unknown locations. Bennett and Lind, “The Collapse of North Korea,” pp. 100–101.

22. 

See Scott L. Kastner, “Is the Taiwan Strait Still a Flash Point? Rethinking the Prospects for Armed Conflict between China and Taiwan,” International Security, Vol. 40, No. 3 (Winter 2015/16), pp. 54–92, doi:10.1162/ISEC_a_00227; Bennett and Lind, “The Collapse of North Korea”; and Evan Braden Montgomery, “Contested Primacy in the Western Pacific: China's Rise and the Future of U.S. Power Projection,” International Security, Vol. 38, No. 4 (Spring 2014), pp. 115–149, doi:/10.1162/ISEC_a_00160.

23. 

See Jonathan D. Pollack and Chung Min Lee, Preparing for Korean Unification: Scenarios and Implications (Washington, D.C.: RAND Corporation, 1999); O'Hanlon, “North Korea Collapse Scenarios”; Robert D. Kaplan, “When North Korea Falls,” Atlantic, October 2006, pp. 64–66, 68, 70–73; Bennett, Preparing for the Possibility of a North Korean Collapse; and Bennett and Lind, “The Collapse of North Korea.”

24. 

This conclusion is based on interactions, workshops, and interviews with relevant units at the Pentagon, U.S. Forces Korea, U.S. Pacific Command, and relevant intelligence agencies.

25. 

John A. Vasquez and Ashlea Rundlett, “Alliances as a Necessary Condition of Multiparty Wars,” Journal of Conflict Resolution, Vol. 60, No. 8 (December 2016), pp. 1395–1418, doi:10.1177/0022002715569770; Renato Corbetta and William J. Dixon, “Multilateralism, Major Powers, and Militarized Disputes,” Political Research Quarterly, Vol. 57, No. 1 (March 2004), pp. 5–14, at p. 12, doi:10.1177/106591290405700101; and Mark J. Mullenbach and Gerard P. Matthews, “Deciding to Intervene: An Analysis of International and Domestic Influences on United States Interventions in Intrastate Disputes,” International Interactions, Vol. 34, No. 1 (March 2008), pp. 25–52, doi:10.1080/ 03050620701878835.

26. 

See Jacob D. Kathman, “Civil War Contagion and Neighboring Interventions,” International Studies Quarterly, Vol. 54, No. 4 (December 2010), pp. 989–1012, doi:10.1111/j.1468-2478.2010.00623.x; Alan Dowty and Gil Loescher, “Refugee Flows as Grounds for International Action,” International Security, Vol. 21, No. 1 (Summer 1996), pp. 43–71, doi:10.2307/2539108; and Barry R. Posen, “Military Responses to Refugee Disasters,” International Security, Vol. 21, No. 1 (Summer 1996), pp. 72–111, doi:10.1162/isec.21.1.72.

27. 

Martin B. Malin, “The Effectiveness and Legitimacy of Using Force to Prevent Nuclear Proliferation,” in Christopher Daase and Oliver Meier, eds., Arms Control in the 21st Century: Between Coercion and Cooperation (New York: Routledge, 2012), pp. 81–122; Jonathan Hunt, “How Weapons of Mass Destruction Became ‘Red Lines’ for America,” Atlantic, April 15, 2017, https://www.theatlantic.com/international/archive/2017/04/america-trump-kennedy-syria-atomic-war/523092/; and “Israel Ready to Act on Syria Weapons, Warns Netanyahu,” BBC, April 18, 2013, https://www.bbc.co.uk/news/world-middle-east-22195508.

28. 

Jun Koga, “Where Do Third Parties Intervene? Third Parties’ Domestic Institutions and Military Interventions in Civil Conflicts,” International Studies Quarterly, Vol. 55, No. 4 (December 2011), pp. 1143–1166, at p. 1144, doi:10.1111/j.1468-2478.2011.00684.x.

29. 

Jacob D. Kathman, “Civil War Diffusion and Regional Motivations for Intervention,” Journal of Conflict Resolution, Vol. 55, No. 6 (December 2011), pp. 847–876, doi:10.1177/0022002711408009; and Kristian Skrede Gleditsch, Idean Salehyan, and Kenneth Schultz, “Fighting at Home, Fighting Abroad: How Civil Wars Lead to International Disputes,” Journal of Conflict Resolution, Vol. 52, No. 4 (August 2008), pp. 479–506, at p. 481, doi:10.1177/0022002707313305.

30. 

Paul F. Diehl and Gary Goertz, War and Peace in International Rivalry (Ann Arbor: University of Michigan Press, 2000); and Mi Yung Yoon, “Explaining U.S. Intervention in Third World Internal Wars, 1945–1989,” Journal of Conflict Resolution, Vol. 41, No. 4 (August 1997), pp. 580–602, doi:10.1177/0022002797041004005.

31. 

This is a less attractive option, however, when the target state and patron do not share preferences or when the patron cannot effectively monitor and sanction agent behavior. See Idean Salehyan, Kristian Skrede Gleditsch, and David E. Cunningham, “Explaining External Support for Insurgent Groups,” International Organization, Vol. 65, No. 4 (Fall 2011), pp. 714–715, doi:10.1017/S0020818311000233.

32. 

Frederic S. Pearson, Robert A. Baumann, and Jeffrey J. Pickering, “Military Intervention and Realpolitik,” in Frank W. Wayman and Paul F. Diehl, eds., Reconstructing Realpolitik (Ann Arbor: University of Michigan Press, 1994), pp. 205–225.

33. 

Patrick M. Regan, Civil Wars and Foreign Powers: Outside Intervention in Intrastate Conflict (Ann Arbor: University of Michigan Press, 2002); and Aysegul Aydin, “Where Do States Go? Strategy in Civil War Intervention,” Conflict Management and Peace Science, Vol. 27, No. 1 (January 2010), pp. 47–66, doi:10.1177/0738894209352128.

34. 

Oriana Skylar Mastro, “Why China Won't Rescue North Korea: What to Expect If Things Fall Apart,” Foreign Affairs, Vol. 97, No. 1 (January/February 2018), pp. 58–66.

35. 

Nuclear Threat Initiative, “CNS North Korea Missile Test Database” (Monterey, Calif.: James Martin Center for Nonproliferation Studies, May 4, 2018), accessed May 4, 2018, http://www.nti.org/analysis/articles/cns-north-korea-missile-test-database/; and Ian Williams, “North Korean Missile Launches and Nuclear Tests: 1984-Present” (Washington, D.C.: Center for Strategic and International Studies, April 20, 2017), accessed June 15, 2018, https://missilethreat.csis.org/north-korea-missile-launches-1984-present/.

36. 

Stephen Chen, “Chinese Scientists Warn North Korea about Disaster Threat at Nuclear Test Site,” South China Morning Post, October 27, 2017, https://www.scmp.com/news/china/society/article/2117340/chinese-scientists-warn-north-korea-about-disaster-threat-nuclear.

37. 

This paragraph was previously published in Oriana Skylar Mastro, “What China Gained from Hosting Kim Jung Un,” Foreign Affairs, April 9, 2018, https://www.foreignaffairs.com/articles/china/2018-04-09/what-china-gained-hosting-kim-jong-un.

38. 

“Xi Jinping zai Hanguo Guoli Shou'er Daxue fabiao zhongyao yanjiang” (Xi Jinping delivers a speech at Seoul National University), Xinhua, July 4, 2014, http://news.xinhuanet.com/world/2014-07/04/c_1111468087.htm.

39. 

Zhao Ma, “War Remembered, Revolution Forgotten: Recasting the Sino-North Korean Alliance in China's Post-Socialist Media State,” Cross-Currents: East Asian History and Culture Review, e-Journal No. 22 (March 2017), pp. 54–82, https://cross-currents.berkeley.edu/e-journal/issue-22/ma.

40. 

See “Sheping: yuelaiyueduo Zhongguoren zhengzai gaibian dui chaoxian kanfa” (Editorial: more and more Chinese change their views on North Korea), Huanqiu Shibao, February 15, 2016, http://opinion.huanqiu.com/editorial/2016-02/8536686.html. In a September 2016 poll, 73.7 percent of respondents thought that China should reconsider the idea of North Korea as a buffer state. “Nirenwei ‘Chaoxian shi Zhongguo de pingzhang’ de guannian gai fansi ma?” (Should the idea, “North Korea is China's buffer,” be reevaluated?), Huanqiu Shibao, February 15, 2016, http://opinion.huanqiu.com/editorial/2016-02/8536686.html; and “Chaoxian heshiyan weihe chikui zuida de shi Zhongguo” (Why China is the biggest loser in North Korea nuclear tests), Souhu Pinglun, September 10, 2016, http://star.news.sohu.com/20160910/n468127784.shtml.

41. 

See “Zhonggong Dangxiao xuezhe: Zhongguo yinggai fangqi Chaoxian” (Chinese Communist Party scholar: China should abandon North Korea), BBC Chinese, February 28, 2013, http://www.bbc.com/zhongwen/simp/press_review/2013/02/130228_press_china_korea_ana.shtml; “Zhongguo xuezhe, Beijing de Chaoxian zhengce hen shibai” (Chinese scholars, Beijing's North Korea policy is a total failure), New York Times Chinese, April 19, 2017, https://cn.nytimes.com/asia-pacific/20170419/china-north-korea-war/?mcubz=0; Yan Xuetong, “Zhongguo jueqi mianlin de anquan zhanlue tiaozhan” (The security strategy challenge China faces in its rise), Huanqiu Shibao, February 23, 2017, http://opinion.china.com.cn/opinion_9_158209.html; “Sheping: yuelai yueduo Zhongguoren zhengzai zhuanbian dui Chaoxian kanfa;” and Chris Buckley, “Excerpts from a Chinese Historian's Speech on North Korea,” New York Times, April 18, 2017.

42. 

Ankit Panda, “China and North Korea Have a Mutual Defense Treaty, but When Would It Apply?” Diplomat, August 14, 2017, http://thediplomat.com/2017/08/china-and-north-korea-have-a-mutual-defense-treaty-but-when-would-it-apply/.

43. 

Wang Haiyun, “Miandui bandao jushi, fanzhan ye xu beizhan” (Facing the situation on the Korean Peninsula: we should prepare for both defensive and offensive measures), Huanqiu Shibao, March 21, 2017, http://opinion.huanqiu.com/1152/2017-03/10344703.html.

44. 

Qiao Zhongwei, Wang Jiasheng, and Zou Hao, Bianjing weiji yingji kongzhi (Emergency control in a border crisis) (Beijing: Junshi Kexue Chubanshe, 2013), p. 70.

45. 

Qiao, Wang, and Zou, Bianjing weiji yingji kongzhi, pp. 163–164. Although the document suggests 100 kilometers, this is unlikely, as it would place significantly large political and industrial centers inside the buffer zone, which would be politically unacceptable. An interior checkpoint at 25 kilometers that mimics the current setup along the border with Burma is more likely.

46. 

Ren Hongsheng, “Bianjing ‘Nanmin ji feifa rujing zhe’ wenti yu Zhongguo de yingdui celve yanjiu” (A study of “refugee and illegal immigrants” issue and China's strategy to deal with it), Guoji Zhanwang, Vol. 9, No. 5 (2017), p. 60.

47. 

Posen, “Military Responses to Refugee Disasters.”

48. 

Lu Hui, Jundui chuzhi tufa shijian xingdong yanjiu (A study of military emergency response operations) (Beijing: Haichao Chubanshe, 2009), p. 313. This point was made broadly, not specifically in relation to a North Korea contingency. Qiao Zhongwei, Wang Jiasheng, and Zou Hao, however, note that China may have to deal with scattered but armed North Korean troops and even organized military forces attempting to cross its border. See Qiao, Wang, and Zou, Bianjing weiji yingji kongzhi, pp. 10–11.

49. 

Bonds et al., Strategy-Policy Mismatch, p. 53, fig. 4.5. See also Oriana Skylar Mastro, “China's Role in North Korea Contingencies,” testimony before the U.S.-China Economic and Security Review Commission, April 12, 2018 (Washington, D.C., Government Printing Office, 2018), https://www.uscc.gov/Hearings/china%E2%80%99s-role-north-korea-contingencies-video.

50. 

Deng Xiaoci, “China Should Prepare to Defend against War in Korean Peninsula, Says Expert,” Global Times, December 17, 2017, http://www.globaltimes.cn/content/1080722.shtml; and Jane Perlez, “Fearing the Worst, China Plans Refugee Camps on North Korean Border,” New York Times, December 11, 2017.

51. 

Wang Hongguang, “Zhongjiang: Chaoxian ruo bengkui Zhongguo jiubuliao Zhongguo bubi wei Chaoxian dazhang” (General: China can't save North Korea from collapse, China does not have to fight for North Korea), Huanqiu Shibao, December 1, 2014, https://www.guancha.cn/internation/2014_12_01_302090_2.shtml.

52. 

Buckley, “Excerpts from a Chinese Historian's Speech on North Korea.”

53. 

Liu Zhen, “China ‘Must Prepare for War over North Korea's Rocket Launch and Nuclear Tests,'” South China Morning Post, February 16, 2016, http://www.scmp.com/news/china/diplomacy-defence/article/1913511/china-must-prepare-war-over-north-koreas-rocket-launch.

54. 

“Zhongguo jiangjian heyingji jiuyuandui” (China soon to create troops for national nuclear emergency preparedness), Renmin Wang, January 28, 2016, http://politics.people.com.cn/n1/2016/0128/c1001-28090637.html.

55. 

Wei Tian, “Jiedu Zhongguo heyingji jiuyuandui” (Understanding China's nuclear emergency response team), Shengming yu Zaihai, November 2016, p. 18; and Guojia yuanzineng jigou (China Atomic Energy Authority), “Zhongguo heyingji gongzuo chengjiu ji weilai zhanwang” (The achievement and prospects of China's nuclear emergency development), Guofang Keji Gongye, Vol. 2 (February 2016), p. 16.

56. 

See Warwick J. McKibbin et al., “Modelling the Economic Impacts of Korean Unification” (Washington, D.C.: Brookings Institution, 2017), https://www.brookings.edu/research/modelling-the-economic-impacts-of-korean-unification/; Charles Wolf Jr. and Kamiljon T. Akramov, North Korean Paradoxes: Circumstances, Costs, and Consequences of Korean Unification (Washington, D.C.: RAND Corporation, 2005); James Pethokoukis, “North Korea's Horrific Economy and the Cost of Reunification,” AEI Ideas, December 19, 2011, http://www.aei.org/publication/north-koreas-horrific-economy-and-the-cost-of-reunification/; and Rachael Revesz, “North Korea Crisis: Re-unification Alone ‘Would Cost $3 Trillion’ after War, Professor Says,” Independent UK, April 30, 2017, http://www.independent.co.uk/news/world/asia/north-south-korea-reunification-kim-jong-un-dictator-donald-trump-president-nuclear-war-ballistic-a7710001.html.

57. 

Adam Taylor, “The Messy Data behind China's Growing Trade with North Korea,” Washington Post, July 5, 2017.

58. 

Author interviews in Shanghai and Beijing, June-August 2016; and Raymond Farrell, “Thunder Run to Seoul: Assessing North Korea's War Plan,” Modern War Institute, April 25, 2017, https://mwi.usma.edu/thunder-run-seoul-assessing-north-koreas-war-plan/.

59. 

Central Intelligence Agency, “South Korea,” The World Factbook, last updated August 28, 2018 (Washington D.C.: Central Intelligence Agency, 2018), https://www.cia.gov/library/publications/the-world-factbook/geos/ks.html.

60. 

Robert E. Kelly, “China and the Unification of the Korean Peninsula (Part 2): A Rising Cost for Beijing,” Lowy Interpreter, September 13, 2017, https://www.lowyinstitute.org/the-interpreter/china-and-unification-korean-peninsula-part-2-rising-cost-beijing

61. 

Sungmin Cho, “What Have Chinese Said and Written about Korean Unification? Discourse Analysis of Chinese Texts on the Unification of Korea,” working paper, Georgetown University, 2017, p. 7.

62. 

Author interview with official at the Ministry of Commerce, Beijing, April 2006.

63. 

Jia Hao and Zhuang Qubing, “China's Policy toward the Korean Peninsula,” Asian Survey, Vol. 32, No. 12 (December 1992), p. 1147, doi:10.2307/2645043.

64. 

Author interview with official at the Ministry of Commerce, Beijing, April 2006.

65. 

Mastro, “China's Role in North Korea Contingencies.” Given the geostrategic importance of the Korean Peninsula to Chinese power, influence, and security, China has consistently intervened in an attempt to counter other actors’ influence there. See Stephen R. Turnbull, The Samurai Invasion of Korea, 1592–98 (Oxford: Osprey, 2008); and S.C.M. Paine, The Sino-Japanese War of 1894–1895: Perceptions, Power, and Primacy (Cambridge: Cambridge University Press, 2003).

66. 

Author interviews in Shanghai and Beijing, June-August 2016. U.S. military officials with firsthand experience working with the South Koreans have commented that at least the second scenario is a valid concern.

67. 

Michelle Ye Hee Lee, “More Than Ever, South Koreans Want Their Own Nuclear Weapons,” Washington Post, September 13, 2017.

68. 

Author interviews in Shanghai and Beijing, June-August 2016.

69. 

Wu Zhicheng and Hong Jianjun, “Some Personal Thoughts on Peace and Security in the Korean Peninsula,” Contemporary International Relations, Vol. 23, No. 6 (December 2013), pp. 31–37, at p. 32.

70. 

Eric Heginbotham et al., An Interactive Look at the U.S.-China Military Scorecard: Forces, Geography, and the Evolving Balance of Power, 1996–2017 (Santa Monica, Calif.: RAND Corporation, 2015); and Office of the Secretary of Defense, Annual Report to Congress: Military and Security Developments Involving the People's Republic of China, 2017 (Washington, D.C.: U.S. Department of Defense, May 2017), https://www.defense.gov/Portals/1/Documents/pubs/2017_China_Military_Power_Report.PDF.

71. 

Mastro, “China's Role in North Korea Contingencies.”

72. 

Correspondence with Dennis J. Blasko (U.S. Army, Ret.), September 4, 2017. These are only estimates, and they may change with the reorganization. Also, only two of the group armies are stationed in provinces that border North Korea.

73. 

Correspondence with Dennis J. Blasko; Peter Wood, “Strategic Assessment: China's Northern Theatre Command” (Washington, D.C.: Jamestown Foundation, May 15, 2017), https://james-town.org/program/strategic-assessment-chinas-northern-theater-command/; and “Kongjiang-bingjun hengkong chushi: kongjun kongjiangbing budui yi huagui beibu zhanqu” (Airborne army established overnight: the airborne army of the air force now belongs to Northern Theater Command), Fenghuang Xinwen, May 3, 2017, https://share.iclient.ifeng.com/news/shareNews?forward=1&aid=122090558.

74. 

“Shipai Wuzhi10 Zhishengjiqun Jilinsheng Shidan Yanlian” (On recent live-fire exercises with the Z-10 in Jilin), Zhongguo Junwang, June 16, 2017, http://jl.news.163.com/17/0616/10/CN1VA4AU04118E6J.html. There is no mention of the purpose of the drill in Jilin, but similar drills conducted in the southern command have been noted in the following source to be for low-penetration missions. See “Shushao Shashou Wuzhi 10 biandui yanlian chaodikong tufang” (Killer of the treetops: On Z-10 formation drills on ultra-low altitude defense), Tengxun Xinwen, August 10, 2017, http://news.qq.com/a/20170810/013677.htm#p=2.

75. 

Correspondence with Dennis J. Blasko.

76. 

Mastro, “China's Role in North Korea Contingencies.”

77. 

Kristin Huang, “Chinese Navy Keeps Firm Focus on Northern Shores as North Korean Tensions Rise,” South China Morning Post, September 7, 2017, http://www.scmp.com/news/china/diplomacy-defence/article/2110233/chinese-navy-keeps-firm-focus-northern-shores-north. See also Oriana Skylar Mastro, “Why Xi Jinping Wants to Broker the Trump-Kim Deal,” National Interest, March 28, 2018, https://nationalinterest.org/feature/why-xi-jinping-wants-broker-the-trump-kim-deal-25118.

78. 

Kinling Lo, “China ‘Shoots Down Incoming Missiles’ during Exercise over Waters Close to North Korea,” South China Morning Post, September 5, 2017, http://www.scmp.com/news/china/diplomacy-defence/article/2109907/china-shoots-down-incoming-missiles-during-exercise.

79. 

Kristin Huang, “Chinese Navy Keeps Firm Focus on Northern Shores as North Korean Tensions Rise,” South China Morning Post, September 7, 2017, http://www.scmp.com/news/china/diplomacy-defence/article/2110233/chinese-navy-keeps-firm-focus-northern-shores-north.

80. 

This assumes that China can avoid conflict with the United States on the peninsula. On China's lack of operational experience and desire for opportunities to test its new capabilities, see Kristen Gunness, “PLA Expeditionary Capabilities and Implications for United States Asia Policy: Testimony before the U.S.-China Economic and Security Review Commission” (Santa Monica, Calif.: RAND Corporation, January 21, 2016), https://www.rand.org/pubs/testimonies/CT452.html.

81. 

See Joel Wuthnow, “‘A Brave New World for Chinese Joint Operations,'” Journal of Strategic Studies, Vol. 40, Nos. 1–2 (February 2017), pp. 169–195, doi:10.1080/01402390.2016.1276012; and Roger Cliff, China's Military Power: Assessing Current and Future Capabilities (New York: Cambridge University Press, 2015).

82. 

Liu Zhen, “China ‘Must Prepare for War over North Korea's Rocket Launch and Nuclear Tests,'” South China Morning Post, February 17, 2016, http://www.scmp.com/news/china/diplomacy-defence/article/1913511/china-must-prepare-war-over-north-koreas-rocket-launch.

83. 

Wood, “Strategic Assessment”; and “Wojun jiang jixu kaizhan zhenduixing yanlian he xinxing wuqi zuozhan jianyan” (PLA will continue conducting targeted exercises and new weapons combat testing), Zhonghua Renmin Gongheguo Guofangbu (Ministry of National Defense of the PRC), April 27, 2017, http://www.mod.gov.cn/info/2017-04/27/content_4779504.htm.

84. 

Chinese interviewees all made this point, though it is difficult to confirm given the sensitive nature of such plans. There have been some leaks as well, but I cannot independently confirm their authenticity. See Shannon Tiezzi, “Does China Have a Contingency Plan for North Korea?” Diplomat, May 7, 2014, http://thediplomat.com/2014/05/does-china-have-a-contingency-plan-for-north-korea/; “Zhongguo ‘xiaoji jihua’ baoguang: meiguo da chaoxian Zhongguo jiu chubing” (Revealing the PLA's “Chick Plan”: China will dispatch as soon as American troops attack North Korea), Xilu, February 18, 2016; and Ryan Browne and Elise Labott, “U.S. Official: With Eye on North Korea, China Puts Bombers on ‘High’ Alert,” CNN, April 20, 2017, http://www.cnn.com/2017/04/20/politics/us-north-korea-china/index.html?sr=twCNN042017us-north-korea-china0524PMVODtopLink&linkId=36711346.

85. 

There are only two main avenues of approach by land for mechanized units along the coasts—a wider one along the western coast and a narrower one on the eastern coast—with very mountainous terrain in the center of the country and few roads. The mountains also make lateral communication among units extremely difficult. Therefore, a simple north to south ground movement is unlikely. It is more likely that China may move some forces in through those routes and supplement them with forces brought in by sea and airborne units.

86. 

Mastro, “China's Role in North Korea Contingencies.”

87. 

Qiao, Wang, and Zou, Bianjing weiji yingji kongzhi, pp. 34, 113.

88. 

The author would like to thank Mark Stokes (U.S. Air Force, Ret.) for these insights.

89. 

Chi Bo and Zhao Lei, “Beibu zhanqu lujun mou bianfanglv ‘dianzi shaobing’ liaowang qianli bianguan” (The “Electronic Guard” has an eye on the borders in the Northern Theater Command Border Defense Brigade), Junbao Jizhe, May 31, 2017, http://bb.81.cn/dbjsxw/content_7622932.htm; and “Beibu zhanqu mou bianfanglv: dahao bianjing guankong ‘zuhequan'” (The “Combination Blow” of Northern Theater Command Border Defense Brigade), Zhongguo Junshi, July 8, 2017, http://item.btime.com/063dt30nu49o6sqiambh854c5ce.

90. 

Bonds et al., Strategy-Policy Mismatch, p.11.

91. 

Bennett and Lind, “The Collapse of North Korea.” See also Mastro, “China's Role in North Korea Contingencies.”

92. 

Author interviews in Shanghai and Beijing, June-August 2016.

93. 

“Chaoxian bandao weiji jing yu Zhou Yongkang xiemi youguan” (Crisis on Korean Peninsula related to Zhou Yongkang giving away secret), Duowei Xinwen, April 18, 2017, http://blog.dwnews.com/post-946878.html; and “Demei cheng Shiluode zhengfu tong Zhongguo gao qingbao hezuo” (German media reveals that Schroeder cooperated with China on Intelligence), Huanqiu Shibao, August 12, 2013, http://world.huanqiu.com/exclusive/2013-08/4232581.html.

94. 

Liu Xiangyang et al., “Feizhanzheng junshi xingdong tanyao” (An examination of MOOTW), Zhongguo Junshi Kexue, No. 3 (2008), p. 34; and Andrew Scobell and Mark Cozad, “China's North Korea Policy: Rethink or Recharge?” Parameters, Vol. 44, No. 1 (Spring 2014), pp. 51–63, at p. 60. There are indications that the PLA is training to engage in radiation monitoring, contamination inspection, and decontamination. See “Shendun—2015 guojiaji heyingji yanxi zai jing juxing” (2015 national-level nuclear emergency exercise Shendun held in Beijing), Guojia Heanquan Ju, June 29, 2015, http://nnsa.mep.gov.cn/zhxx_8953/gzdt/201506/t20150629_305352.html.

95. 

See also Mastro, “China's Role in North Korea Contingencies.” In 2004, defense along the North Korean border was transferred to the PLA to improve border defense infrastructure and practices. In wartime, however, mission control could again be transferred. Chang Wanquan, “04 niandi Zhongchao bianfang you gongan yijiao jiefangjun” (The China-NK border control has been put in the charge of the PLA instead of the police since the end of 2004), Huanqiu Shibao, January 7, 2009, http://mil.huanqiu.com/china/2009-01/337575.html.

96. 

The discussion of the training is in the context of nuclear emergency rescue. See Lu, Jundui chuzhi tufa shijian xingdong yanjiu, p. 157; and “Woguo shouci heshigu yingji yanxi ‘Shendun 2009’ chenggong juxing” (China's first nuclear accident emergency exercise “Shendun 2009” was successfully held), Zhonghuarenmin Gongheguo Gongye he Xinxihua Bu (Ministry of Industry and Information Technology of the People's Republic of China), November 10, 2009, http://www.miit.gov.cn/n1146285/n1146352/n3054355/n3057511/n3057519/c3603205/content.html.

97. 

This information was gleaned from discussions and exhibits at China's Nuclear Center for Excellence in Beijing.

98. 

Mastro, “China's Role in North Korea Contingencies.” Unfortunately, very little open-source literature has discussed in detail what this role would be. Di'er paobing zhanyi xue (The science of Second Artillery campaigns) (Beijing: Jiefangjun Chubanshe, 2004), the most authoritative work on Second Artillery doctrine (the predecessor to the Strategic Rocket Force), does not discuss topics relevant to WMD-C3D. The Strategic Rocket Force is likely to play some role, however, given that it is in charge of Chinese nuclear weapons. Also, its units conducted a drill in Northwest China in August 2017 on how to deal with nuclear pollution that could result from North Korean nuclear testing or use. Tang Di, “Heweixie pozaimeijie Zhonggong huojianjun yanlian hewuran yingji jiuyuan” (Faced with urgent nuclear threats, China SRF conducts exercises on nuclear pollution), Xintangren Dianshitai, August 17, 2017, http://ca.ntdtv.com/xtr/gb/2017/08/17/a1338326.html.

99. 

State Council Information Office of the People's Republic of China, China's Nuclear Emergency Preparedness (Beijing: People's Republic of China, January 2016), http://english.gov.cn/archive/white_paper/2016/01/27/content_281475279484672.htm.

100. 

State Council Information Office of the People's Republic of China, China's Nuclear Emergency Preparedness. There are now also three national-level nuclear emergency response training bases, which essentially form an integrated emergency technical support and training system. Lu, Jundui chuzhi tufa shijian xingdong yanjiu, p. 157.

101. 

“Shendun-2015 Guojia heshigu yingji lianhe yanxi chenggong juxing” (Shendun-2015 national-level nuclear emergency exercise successfully held), Zhonghuarenmin Gongheguo Gongye he Xinxihua Bu (Ministry of Industry and Information Technology of People's Republic of China), June 26, 2016, http://www.miit.gov.cn/n1146285/n1146347/n1147601/n1147604/c3468215/content.html. Zheng Weibo, director of the Office of Emergency Response of the Combatant Command in the PLA General Staff, was the deputy general director of the 2015 Shendun exercise. It is unclear whether the military had a general-director-level position in the 2009 Shendun exercise.

102. 

Zhang Hui, “China's Nuclear Security: Progress, Challenges, and Next Steps” (Cambridge, Mass.: Belfer Center for Science and International Affairs, Harvard Kennedy School, March 2016), p. 2, http://www.belfercenter.org/sites/default/files/files/publication/Chinas%20Nuclear%20Security-Web.pdf; and NTI Nuclear Security Index, “Building a Framework for Assurance, Accountability, and Action,” 4th ed. (Washington, D.C.: Nuclear Threat Initiative, September 2018), p. 64.

103. 

One would imagine that security would be strengthened in a combat scenario. See Pan Ziqiang, ed., He yu fushe kongbu shijian guanli (Nuclear and radioactive terrorist crisis management) (Beijing: Kexue Chubanshe, 2005), pp. 62, 69.

104. 

Qiao, Wang, and Zou, Bianjing weiji yingji kongzhi, p. 202.

105. 

Zhang, “China's Nuclear Security,” p. 2.

106. 

Mastro, “China's Role in North Korea Contingencies.”

107. 

Author interviews in Shanghai and Beijing, June-August 2016.

108. 

Ibid.

109. 

For operational scenarios, see Bennett and Lind, “The Collapse of North Korea”; and Bennett, Preparing for the Possibility of a North Korean Collapse.

110. 

This is my evaluation after discussing the issue with approximately two dozen Department of Defense planners and strategists from December 2016 to May 2017.

111. 

These were the main arguments made during my interviews and workshops with U.S Department of Defense and military officials from December 2016 to May 2017.

112. 

For more on these changes, see Mastro, “Why China Won't Rescue North Korea.”

113. 

Timothy Bonds et al., “Closing the Strategy-Policy Gap in Countering Weapons of Mass Destruction” (Santa Monica, Calif.: RAND Corporation, 2014).

114. 

Author interviews in Shanghai and Beijing, June-August 2016.

115. 

For an analysis of how the United States might conduct this operation, see Peters and Carus, “Interagency and Intra-Agency Aspects of U.S. Elimination Activities,” p. 109.

116. 

Bonds et al., Strategy-Policy Mismatch, p. xvi.

117. 

Using South Korean troops is not a viable option to resolve the manpower issue. They cannot conduct most aspects of WMD-C3D, as they are not authorized to do so under the Nuclear Nonproliferation Treaty. South Korean forces could potentially help with site exploitation and characterization, but this is currently pending U.S. State Department approval.

118. 

Lt. Col. Scott Daulton and Lt. Col. Bill Shavce, “The Challenge of Countering Weapons of Mass Destruction on the Korean Peninsula,” Military Review, November/December 2014, pp. 47–53, at p. 51.

119. 

Author interviews in Shanghai and Beijing, June-August 2016.

120. 

For a discussion of the complications associated with this assumption, see Lt. Col. Sean Crockett, “Reconsidering U.S. Post-Conflict Policy in Weapons of Mass Destruction (WMD) States” (Carlisle, Pa.: Strategy Research Project, U.S. Army War College, January 4, 2016).

121. 

Author interviews in Shanghai and Beijing, June-August 2016. See also Mastro, “China's Role in North Korea Contingencies.” In addition to providing expertise and manpower, the IAEA may provide political cover for Beijing to participate in a WMD-E mission in North Korea. IAEA involvement in the accounting process protects the United States and South Korea from accusations of, for example, malfeasance. The author would like to thank an anonymous reviewer for this point.

122. 

Although this article focuses on U.S.-China dynamics and each country's WMD-C3D capabilities, South Korean preferences could complicate U.S. efforts to effectively manage Chinese intervention. The South Korean government is unlikely to support bilateral precrisis coordination, let alone military cooperation, during a contingency. South Korea may be concerned that agreeing to a larger Chinese role would reduce South Korea's influence and perhaps even exclude both Koreas from some great power accommodation. See Lee Ji-young, “THAAD Deployment and Korea-China Relations” (Seoul: Institute of Foreign Affairs and National Security, February 29, 2016).

123. 

This is a common assumption. See, for example, see Victor D. Cha, “What Do They Really Want? Obama's North Korea Conundrum,” Washington Quarterly, Vol. 32, No. 4 (October 2009), pp. 119–138, at p. 129, doi:10.1080/01636600903224837.

124. 

Jane Perlez, “North Korea's Nuclear Arsenal Threatens China's Path to Power,” New York Times, September 5, 2017. The United States could also loosen some of the regulations that stopped cooperation between U.S. and Chinese scientists, laboratories, and facilities in the 1990s. The China Atomic Energy Authority regulates both civilian and military sectors, however, and it does participate in discussions with the United States. See also Zhang, “China's Nuclear Security.”

125. 

Office of the Press Secretary, “Joint Statement on U.S. China Cooperation 2016” (Washington, D.C.: White House, March 31, 2016), https://obamawhitehouse.archives.gov/the-press-office/2016/03/31/us-china-joint-statement-nuclear-security-cooperation.

126. 

For example, China participated in IAEA exercises in 2005, 2006, and 2013. See “Zhongguo canjia IAEA daguimo heyingji yanxi” (China took part in IAEA exercises), Zhonghuarenmin Gongheguo Zhongyangrenmin Zhengfu (Central People's Government of the PRC), May 11, 2005, http://www.gov.cn/yjgl/2005-05/11/content_31081.htm; “Guojia Heyingji Bangongshi canjia Guoji Heyuanzineng Jigou yingji yanxi” (National Nuclear Emergency Office took part in IAEA exercises), Zhonghuarenmin Gongheguo Zhongyang Renmin Zhengfu (Central People's Government of the PRC), November 21, 2006, http://www.gov.cn/gzdt/2006-11/21/content_448715.htm; and “Guoji Hefushe shijian yingji tongxun yanxi” (International nuclear radiation incident emergency communications exercises), Guojia weishengjishengwei heshigu yixue yingji zhongxin (Chinese Center for Medical Response to Radiation Emergency), November 25, 2013, http://www.nirp.cn/htm/article507.htm.

127. 

Office of the Press Secretary, “Joint Statement on U.S. China Cooperation 2016.”

128. 

See also Oriana Skylar Mastro, China's Evolving North Korea Strategy (Washington, D.C., United States Institute of Peace, September 2017), https://www.usip.org/sites/default/files/PB231-Chinas-evolving-north-korea-strategy.pdf; “Zhongguo shouci juban heshigu yingji yanxi” (China for the first time holds nuclear emergency operation), Zibo Shi Yingjiban (Emergency Management Office of Zibo Municipal People's Government), November, 11, 2009, http://www.emo.gov.cn/Article_Show.asp?ArticleID=1616; and “‘Shendun-2015’ Guojia heshigu yingji jin chenggong lianhe yanxi” (“Shendun 2015” China holds the nuclear emergency operation successfully today), Renmin Wang, June 26, 2015, http://scitech.people.com.cn/n/2015/0626/c1007-27213439.html.

129. 

Senate Armed Services Committee Hearing, “Adm. Harris Opening Remarks” (Washington, D.C.: Senate Armed Services Committee, December 2, 2014), http://www.cpf.navy.mil/leaders/harry-harris/speeches/2014/12/sasc-confirmation-hearing.pdf.

130. 

Some examples include participating in counterpiracy operations in the Gulf of Aden, conducting a significant noncombatant evacuation from Yemen, agreeing to send combat troops to Mali with a United Nations peacekeeping operation, and signing agreements for port access with Australia, Djibouti, and Malaysia.