The Deliberate Employment of US Nuclear Weapons: Escalation Triggers on the Korean Peninsula

ABSTRACT This paper focuses on the conditions under which the United States might use nuclear weapons during a war on the Korean Peninsula. It identifies several circumstances that might trigger such a decision, the purposes of a US nuclear strike, and the plausible targets. Attention is focused on the roles that nuclear weapons continue to play in US military operations and foreign policy strategy despite steps to reduce their salience since the end of the Cold War. I argue that the United States would only consider using nuclear weapons if (1) the mission being performed was of critical importance, (2) it could not be accomplished with sufficient certainty or speed with non-nuclear options, and (3) the use of nuclear munitions significantly increased the probability of success. This paper identifies a range of circumstances that could arise during a war in Korea that might satisfy all three criteria, and it identifies the pathways that are most likely to trigger US nuclear employment. Examining these conditions now can help US allies and other partners identify and resolve disagreements about nuclear employment, enhance deterrence against regional adversaries, and shed light on the logic driving important decisions about US nuclear force structure and modernization.