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Exporting the Bomb: Why States Provide Sensitive Nuclear Assistance


Why do states provide sensitive nuclear assistance to nonnuclear weapon states, contributing to the international spread of nuclear weapons? Using a new data set on sensitive nuclear transfers, this article analyzes the determinants of sensitive nuclear assistance. I first describe a simple logic of the differential effects of nuclear proliferation, which I use to generate hypotheses about the conditions under which states provide sensitive nuclear assistance. I then show that the strategic characteristics of the potential nuclear suppliers are the most important determinants of sensitive nuclear assistance. Explanations that emphasize the importance of economic motivations do not find support in the data. This article presents a new approach to the study of the spread of nuclear weapons, focusing on the supply side of nuclear proliferation.

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Matthew Kroenig is Assistant Professor, Georgetown University, Washington, DC 20057 (
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