Assessing Nuclear Proliferation Risk

• In Event: Nuclear Weapons Modernization and Proliferation

Abstract

Countries vary in their risk of nuclear proliferation based on their capabilities, security context, leadership, and other factors. Accurately assessing this risk is important both for nonproliferation policy and for international security scholarship. In academic studies of nuclear proliferation, scholars most often avoid assessing proliferation risk altogether, or else do so only implicitly. Qualitative studies of proliferation, for example, rarely talk about the implicit model of proliferation risk used to filter cases as possibilities for review, raising the possibility that we may miss instructive cases on the margins. Quantitative scholars generally take the opposite approach, explicitly including all states in their analysis—even those with almost no risk of proliferation—calling into question the applicability of their results. In studies of international conflict more broadly, the risk of proliferation by one party or another is often a key omitted variable: an important consideration of international policymakers left out due to measurement challenges. This article develops and validates a new measure of the likelihood that a country will seek nuclear weapons under particular circumstances: the proliferation risk score. Proliferation risk scores are both scalable and flexible. They can be updated with new data and expanded to cover new factors that might lead to nuclear pursuit, and they can be used in a variety of what-if scenarios to identify factors that represent the greatest risk for a specific country in a specific global situation. They can be helpful to policymakers and analysts as a starting point for structured analytic techniques, and to scholars by filling an important gap in studies of international security and conflict.

Author

• Jeff Kaplow, College of William & Mary