How Does Extended Nuclear Deterrence Work?
Extended nuclear deterrence has been at the core of U.S. foreign policy since the end of World War II and remains at the heart of most U.S. alliances. Many of the United States' most important alliances in Europe and Asia include a nuclear dimension, with U.S. nuclear weapons and the threat to use them lurking in the background of U.S. commitments. On the other hand, extended nuclear deterrence is a difficult thing to make credible. This tension is why Professor Mark Bell is drawn to studying extended nuclear deterrence. Extended nuclear deterrence, Bell says, is "essentially a commitment to fight a nuclear war — a nuclear war that might see your own cities destroyed — on behalf of someone else. That's a hard commitment to make work."
How Does Extended Nuclear Deterrence Work?
In his current research, Bell is exploring how extended nuclear deterrence works. He has already done work on aspects of this, including an article in Foreign Affairs entitled "Europe's Nuclear Trilemma," which focused on Europe's nuclear choices in response to emerging fears about the United States' credibility and willingness to defend Europe. He is now examining how extended nuclear deterrence works more generally, and how easy it is to send signals within the context of extended nuclear deterrence.
Bell is interested in exploring questions such as: When the United States sends a signal that it is or is not interested in defending one of its allies, for example, are those signals received by U.S. adversaries in the way the U.S. intends them to be received? Are they received by the ally the U.S. is potentially protecting in the way the U.S. intends? What kinds of arrangements best assure allies that the United States would defend them? What kind of threats best deter adversaries from attacking allies?
Furthermore, Bell is interested in contributing to ongoing debates about how nuclear deterrence works — if it does — and how it might continue to work or not work in the future. This is particularly important for many of the hot-button issues in U.S. foreign policy today relating to NATO, Russia, China, Taiwan, and North Korea.
Research Made Possible
In support of this research, Bell has been awarded the 2026-2028 Social Science Research Grant. Made possible by the Engahl Family Fund, College of Liberal Arts, and the Executive Vice President and Provost, the Social Science Research Grant supports "hard-to-fund" or "rapid response" research. The award assists faculty with gaining access to national scientific data, for conducting pilot research that will enhance competitiveness in external grant competitions, and for faculty to complete fieldwork in fast-moving field situations. Bell is planning to use this grant to both conduct survey research and engage with governments and policymakers on this rapidly shifting policy area.
At present, there are "a lot of doubts about the credibility of U.S. extended nuclear deterrence," says Bell, especially "about whether the U.S. would actually fight any sort of war, let alone a nuclear war, on behalf of its allies." We are also seeing the potential emergence of new extended nuclear deterrence arrangements, as France and Britain consider trying to do more to use their own nuclear weapons to protect countries in Eastern Europe. Pakistan is also thinking about attempting something along these lines with Saudi Arabia. This makes it all the more important to understand how extended nuclear deterrence works in general terms, beyond the U.S. experience.
Bell's research will both generate new scholarly knowledge, while also contributing to crucial ongoing policy debates about one of the most critical and high stakes aspects of international security.
