Abstract: Why do states acquire nuclear weapons? Existing theories of nuclear proliferation fail to account for the impact of bargaining on the process---i.e., credible agreements exist in which rival states make sufficient concessions to convince the potential rising state not to proliferate. I show the existence of that range of settlements and the robustness of the inefficiency puzzle and then provide two main explanations as to why states proliferate anyway. First, if the would-be proliferator expects to lose the ability to construct nuclear weapons in the future, the states face a commitment problem: the rival state would like to promise to continue providing concessions into the future but will renege once proliferation is no longer an option. And second, if the proliferator's rival faces some sort of uncertainty---whether regarding the potential proliferator's ability to go nuclear or regarding its previous proliferation activity---the optimal offer can entail positive probability of nuclear investment. However, the nonproliferation regime's mission to increase the cost of building often leads to Pareto improvement. Put differently, rising states sometimes benefit directly by making their nuclear options more costly.
About the Speaker: William Spaniel received a PhD in international relations, formal theory, and quantitative methodology from the University of Rochester in 2015. His research investigates the credibility of nuclear agreements in the absence of verifiable compliance. As a Stanton Nuclear Security Fellow at CISAC for 2015-2016, he is working on the potentially perverse effects of nuclear safeguards. His publications have appeared in International Studies Quarterly, International Interactions, and The Journal of Theoretical Politics.