The book explains how and why nuclear weapons cooperation between the US and its allies has evolved since the 1950s. By bringing institutional perspectives to the study of how alliances operate, it focuses on the objectives and sources of influence of US allies in Europe and Asia as they cooperate with the US on the world’s most powerful weapons.

Introduction1 Realism, institutionalism, and nuclear weapons cooperation2 Nuclear sharing and mutual dependence: Germany and NATO nuclear weapons cooperation3 Local accommodation: Norway and nuclear weapons cooperation in NATO4 Security at arm’s length: US–Japan nuclear weapons cooperation5 Assurance and abandonment: Nuclear weapons in the US–South Korea alliance6 Informal bargaining: Nuclear weapons cooperation and the US–Australia alliance7 Understanding the drivers of nuclear weapons cooperationIndex

‘This important new study combines historical research, political science, and policy analysis to generate valuable new insights into past and present practices in both Europe and Asia and thereby lays the foundation for future policy development.' Brad Roberts, Director of the Center for Global Security Research at Lawrence Livermore National Laboratory, California 'Partners in deterrence offers a fresh perspective on an enduring question: what motivates states to form nuclear alliances? As US alliances in Europe and Asia face growing nuclear threats, strategists would be well-served to understand what brings in security partners - and what helps them stay. By going beyond the traditional fixation on proximate security threats as the main driver of nuclear alliances, the book widens the aperture of contemporary debates, providing a valuable perspective for academics and policymakers alike.' Matthew Kroenig, Professor of Government and Foreign Service at Georgetown University and the author of The Logic of American Nuclear StrategyFrom the dawn of the atomic age to today, nuclear weapons have been central to the internal dynamics of US alliances in Europe and Asia. But nuclear weapons cooperation in US alliances has varied significantly between allies and over time. Partners in deterrence explores the history of America’s nuclear posture worldwide, delving into alliance structures and interaction during and after the Cold War to uncover the underlying dynamics of nuclear weapons cooperation between the US and its allies.Combining in-depth empirical analysis with an accessible theoretical lens, the book reveals that US allies have wielded significant influence in shaping nuclear weapons cooperation with the US in ways that reflect their own, often idiosyncratic, objectives. Alliances are ecosystems of exchange rather than mere tools of external balancing, Frühling and O’Neil argue, and institutional perspectives can offer an unprecedented insight into how structured cooperation can promote policy convergence.