
What policies has the United States pursued in international security affairs – particularly towards Europe – since taking an active role in world affairs after 1945? What explains the course and conduct of U.S. foreign policy? What are the ramifications of U.S. engagement for the United States, other actors, and international security more generally?
I seek to understand the course, causes, and consequences of U.S. policy in world affairs since 1945. My focus is on leveraging international relations concepts to explain U.S. foreign policy, while revising and assessing IR theory given new empirical discoveries.
I seek to understand the course, causes, and consequences of U.S. policy in world affairs since 1945. My focus is on leveraging international relations concepts to explain U.S. foreign policy, while revising and assessing IR theory given new empirical discoveries.
European Security, NATO Enlargement and U.S. Policy

A major subset of this work examines the politics and repercussions of U.S. efforts to shape European security and, in particular, to enlarge NATO after the Cold War. For example, my award-winning 2016 International Security article provides new archival evidence that the United States assured Soviet leaders at Cold War's end that NATO would not enlarge into Eastern Europe, only to privately consider the opposite. Drawing on research into informal agreements in world politics, the results provide circumstantial evidence that ongoing tensions with Moscow partly stem from lingering Russian mistrust.
Furthermore, I recently co-edited a special issue of International Politics assessing the legacy of NATO enlargement. This builds on a workshop held at BU in May 2019. Here, my solo-authored article examines the drivers behind the United States' sustained support for NATO expansion after the Cold War, and discusses the varied consequences for U.S. national security. I also have a co-authored framing paper highlighting the methodological problems in assessing NATO enlargement's effects and suggesting avenues for research. Another forthcoming co-authored piece reflects on alternatives to NATO enlargement in the 1990s, and their prospective merits and drawbacks.
Other work looks at U.S. policy towards Europe and NATO in earlier periods. Research with John Schuessler in Strategic Studies Quarterly, for instance, challenges claims that the United States' alliance policy is distinguished by U.S. reassurance efforts, by examining U.S. threats to abandon NATO during the Cold War.
Above all, I aim to link this research to contemporary policy debates . Thus, I disseminated findings on the U.S. assurances to the USSR with Foreign Affairs, and have written on the security risks to the United States from NATO expansion for The Washington Quarterly. Similarly, pieces in War On The Rocks and in H-Diplo's ISSF Policy Series assess the Trump administration's approach towards NATO, and situate contemporary developments in historical perspective.
Furthermore, I recently co-edited a special issue of International Politics assessing the legacy of NATO enlargement. This builds on a workshop held at BU in May 2019. Here, my solo-authored article examines the drivers behind the United States' sustained support for NATO expansion after the Cold War, and discusses the varied consequences for U.S. national security. I also have a co-authored framing paper highlighting the methodological problems in assessing NATO enlargement's effects and suggesting avenues for research. Another forthcoming co-authored piece reflects on alternatives to NATO enlargement in the 1990s, and their prospective merits and drawbacks.
Other work looks at U.S. policy towards Europe and NATO in earlier periods. Research with John Schuessler in Strategic Studies Quarterly, for instance, challenges claims that the United States' alliance policy is distinguished by U.S. reassurance efforts, by examining U.S. threats to abandon NATO during the Cold War.
Above all, I aim to link this research to contemporary policy debates . Thus, I disseminated findings on the U.S. assurances to the USSR with Foreign Affairs, and have written on the security risks to the United States from NATO expansion for The Washington Quarterly. Similarly, pieces in War On The Rocks and in H-Diplo's ISSF Policy Series assess the Trump administration's approach towards NATO, and situate contemporary developments in historical perspective.
U.S. Strategy and the End of the Cold War

I strive to connect historiographic conversations with IR theory. American foreign policy at Cold War's end looms large, where I have contributed to a growing effort to re-evaluate U.S. strategy at Cold War's end in light of new archival discoveries.
Thus, a paper for the Woodrow Wilson Center's Cold War International History Project provides new archival evidence that the United States used the Malta Summit of December 1989 to informally bargain with the Soviet Union over the shape of post-Cold War European security. Likewise, a chapter for an Oxford UP volume deploys deterrence and bargaining theory to develop a framework for understanding the dangers that can result when states acquire new strategic interests without commensurate means to defend these interests, illustrating the argument by evaluating U.S. policy during the 1989 East European Revolutions.
Similarly, a piece with Foreign Affairs showcases the growing evidence that U.S. policymakers feared the 1989 Revolutions would trigger a major U.S.-Soviet crisis. More directly, an article with Orbis looks at the realpolitik attitudes among the George H.W. Bush administration as the Cold War ended. Drawing these themes together, another forthcoming chapter with Cambridge UP shows that the United States aimed to create and subsequently extend U.S. preeminence in Europe by exploiting Soviet problems as the Cold War ended.
Thus, a paper for the Woodrow Wilson Center's Cold War International History Project provides new archival evidence that the United States used the Malta Summit of December 1989 to informally bargain with the Soviet Union over the shape of post-Cold War European security. Likewise, a chapter for an Oxford UP volume deploys deterrence and bargaining theory to develop a framework for understanding the dangers that can result when states acquire new strategic interests without commensurate means to defend these interests, illustrating the argument by evaluating U.S. policy during the 1989 East European Revolutions.
Similarly, a piece with Foreign Affairs showcases the growing evidence that U.S. policymakers feared the 1989 Revolutions would trigger a major U.S.-Soviet crisis. More directly, an article with Orbis looks at the realpolitik attitudes among the George H.W. Bush administration as the Cold War ended. Drawing these themes together, another forthcoming chapter with Cambridge UP shows that the United States aimed to create and subsequently extend U.S. preeminence in Europe by exploiting Soviet problems as the Cold War ended.
The Strategic Backdrop of U.S. Foreign Policy
Any discussion of U.S. foreign policy needs to consider the strategic and policymaking backdrop in which the United States operates. The growing U.S. focus on Asian security plays a prominent role in this work. To this end, pieces with Strategic Studies Quarterly and Foreign Affairs utilize research on the sources of international settlements (e.g., the Congress of Vienna) to explore prospects for U.S. negotiations with North Korea over the DPRK nuclear program. Elsewhere, research in The Monkey Cage challenges a growing chorus suggesting that the United States and China are in a "new Cold War." Even more directly, a Foreign Affairs article co-authored with Stephen Wertheim explores the intellectual roots and strategic precepts that seem to undergird President Joe Biden's approach to international affairs.
Along similar lines, a 2011 article in International Security (co-authored with Miranda Priebe) analyzed the military vulnerability of the Saudi Arabian oil network to an Iranian attack, predicting - as events in 2019 vindicated - that Iran's ability to disable the Saudi oil network was limited. Similarly, research with Sameer Lalwani investigated the United States' ability to adopt a different military model to retain command of the global security commons.
Elsewhere, Austin Long and I use insights from bureaucratic politics and principal-agent theories to unpack the intelligence and policymaking problems that hindered American efforts to stop Israel from acquiring nuclear weapons in an article for the Journal of Strategic Studies. Furthermore, a chapter with David Edelstein explores the mechanisms by which states (including the U.S.) can be entrapped by their allies.
Along similar lines, a 2011 article in International Security (co-authored with Miranda Priebe) analyzed the military vulnerability of the Saudi Arabian oil network to an Iranian attack, predicting - as events in 2019 vindicated - that Iran's ability to disable the Saudi oil network was limited. Similarly, research with Sameer Lalwani investigated the United States' ability to adopt a different military model to retain command of the global security commons.
Elsewhere, Austin Long and I use insights from bureaucratic politics and principal-agent theories to unpack the intelligence and policymaking problems that hindered American efforts to stop Israel from acquiring nuclear weapons in an article for the Journal of Strategic Studies. Furthermore, a chapter with David Edelstein explores the mechanisms by which states (including the U.S.) can be entrapped by their allies.