Reflection or Constraint? The NPT and U.S. Policy toward Emerging Nuclear Powers

Nicholas Miller, Associate Professor of Government, Dartmouth College
Encina Hall West, Room 400

Do international treaties constrain great power behavior or merely reflect great power preferences? This paper reexamines this longstanding question by analyzing the impact of the Nuclear Nonproliferation Treaty (NPT) on U.S. policy. The existing literature on the NPT suggests it is not a significant constraint on Washington: either it reflects a vital U.S. interest in preventing the spread of nuclear weapons or the United States selectively enforces the treaty and ignores it when it is inconvenient. In contrast, this paper argues the NPT exerts a significant constraining effect on U.S. policy, in particular by activating and mobilizing domestic actors who push the White House to impose pressure on proliferators even when the President believes this is against U.S. interests. The paper tests and finds preliminary support for four observable implications of the argument, showing that (1) the United States has been more likely to impose sanctions on countries pursuing nuclear weapons after the NPT, (2) this likelihood has increased over time in line with growing domestic mobilization in support of the treaty, (3) Washington has been more likely to try to convince countries that acquire nuclear weapons to roll back their arsenals after the NPT, and (4) this constraining impact is visible even in the case of Pakistan, a case that is often pointed to as one where the United States ignored the NPT and nonproliferation concerns.


Nicholas Miller's research focuses on nuclear proliferation and international security. His book, Stopping the Bomb: The Sources and Effectiveness of U.S. Nonproliferation Policy,  was published by Cornell University Press in 2018. The dissertation on which the book is based received the 2015 Helen Dwight Reid Award, awarded by the American Political Science Association for the best dissertation in international relations, law, and politics. It also won the 2015 Kenneth N. Waltz Prize, awarded for the best dissertation in the field of international security and arms control.