On 4 April 2023, almost three decades after joining the European Union, Finland became a member of the North Atlantic Treaty Organization (NATO). In doing so, the small Nordic country on Europe's northeastern flank became fully integrated into the “institutional West,” shedding more than 70 years of a delicate balancing act between East and West. What, beyond the exogenous shock of Russia's invasion of Ukraine in February 2022, led to this outcome? Using recently declassified Finnish, British, and German documents combined with Soviet sources, this article places Helsinki's policymaking in a wider chronological and international context. It shows how Finland's turn away from neutrality was the culmination of numerous small steps on a difficult, often circuitous, path out of the strictures of the Cold War divides in Europe. Rather than just passively waiting, the Finns pushed quietly but forcefully to remove the limitations on their sovereignty after 1989, when Europe was transformed, Germany was unified, and the Soviet Union ceased to exist. Driven by a strong presidency and bolstered by an overwhelming national consensus, Finland cautiously but firmly maneuvered out of the Russian shadow.

Controversy arose in the mid-1990s when Russian officials accused Western governments of reneging on binding pledges made to Moscow in 1990 during German unification diplomacy. According to the allegations, Western leaders had solemnly promised that the North Atlantic Treaty Organization (NATO) would never expand beyond Germany into Central and Eastern Europe. Were such pledges ever made? Was the Soviet Union betrayed, and if so, by whom, how, and when? Or have various tactical comments been misinterpreted in hindsight? This article seeks to offer new answers to these questions by exploring not simply U.S.-Soviet-West German triangular diplomacy in 1990 but also the evolution of different approaches, ideas, and visions regarding Germany's security arrangements and the wider European security architecture. These ideas were floated publicly and privately, at home and abroad, by Chancellor Helmut Kohl, Foreign Minister Hans-Dietrich Genscher, and other senior West German officials. In showing how ultimately a “unified Germany in NATO” came about after months of intense diplomacy in 1990 to resolve the “German question,” this article refutes the recently made claim that the extension of full membership to the whole of Germany was a precedent-setting expansion of NATO.

On the basis of recently released archival sources from several member-states of the North Atlantic Treaty Organization (NATO), this article revisits the making of NATO's landmark 1979 dual-track decision. The article examines the intersecting processes of personal, bureaucratic, national, and alliance high politics in the broader Cold War context of increasingly adversarial East-West relations. The discussion sheds new light on how NATO tried to augment its deterrent capability via the deployment of long-range theater nuclear missiles and why ultimately an arms control proposal to the Soviet Union was included as an equal strand. The 1979 decision owed most to West German Chancellor Helmut Schmidt's political thought and initiative. Intra-alliance decision-making, marked by transatlantic conflict and cooperation, benefitted from the creativity and agency of West German, British, and Norwegian officials. Contrary to popular impressions, the United States did not truly lead the process.