At least since the U.S. invasion of Iraq in 2003, a subset of realists, conservatives, and progressives have called for greater restraint in U.S. grand strategy. Given that restraint is a key position in the grand strategy debate, this article explores the variations within restraint's big tent in greater detail. Drawing on writings by and interviews with advocates of restraint, we identify the underlying beliefs that have led these disparate groups to converge on restraint. We find that there are competing visions of restraint. Realists want to prevent the emergence of regional hegemons without provoking great power war; conservatives seek to preserve what they identify as the American way of life; and progressives are motivated by the desire to combat inequality and injustice at home and abroad. Even within each group, there are a range of underlying beliefs and foreign policy preferences, and more divisions have emerged in response to the Russian invasion of Ukraine and China's rise. We explore how these groups’ positions may evolve in the future as the threat environment continues to change and new policy questions emerge.

The United States and its Persian Gulf allies have been increasingly concerned with the growing size and complexity of Iran's ballistic missile programs. At a time when the United States and its allies remain locked in a standoff with Iran over the latter's nuclear program, states around the Persian Gulf fear that Iran would retaliate for an attack on its nuclear program by launching missiles at regional oil installations and other strategic targets. An examination of the threat posed by Iran's missiles to Saudi Arabian oil installations, based on an assessment of Iran's missile capabilities, a detailed analysis of Saudi Arabian oil infrastructure, and a simulated missile campaign against the network using known Iranian weapons, finds no evidence of a significant Iranian missile threat to Saudi infrastructure. These findings cast doubt on one aspect of the Iranian threat to Persian Gulf oil while offering an analytic framework for understanding developments in the Iranian missile arsenal and the vulnerability of oil infrastructure to conventional attack.