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The Strategic Logic of Nuclear Proliferation

My article (with Alex Debs) on the strategic logic of nuclear proliferation will be out in the Fall 2014 issue of International Security. You can read the latest draft here. And here is the abstract:

When do states acquire nuclear weapons? This article introduces a strategic theory of nuclear proliferation that takes into account the security goals of all key actors: the potential proliferator, its adversaries, and, when present, its allies. In order to acquire nuclear weapons, we argue, a state must possess both the willingness and the opportunity to proliferate. Willingness requires the presence of a grave security threat that is not covered by a reliable ally. Opportunity requires high relative power vis-à-vis the state’s adversaries or the protection of an ally. While relatively weak states without a powerful ally lack the opportunity to go nuclear, those with a reliable ally that covers all their security goals lack the willingness to do so. Therefore, only powerful states or those protected by an ally that does not reliably cover some of their security goals will acquire the bomb. We evaluate our theory against all historical instances of nuclear development and trace its logic in the Soviet, Iraqi, Pakistani, South Korean, and West German cases. We conclude with implications for the study of proliferation and for U.S. non-proliferation policy.

categories: IR theory, national security, nuclear weapons, publications, research. | tags: , .

Posted at 5:41 pm


Theory of Unipolar Politics

My book Theory of Unipolar Politics is now out on hard cover, paperback, and ebook formats directly from Cambridge University Press or through Amazon.

categories: books, IR theory, publications, research. | tags: , , .

Posted at 4:41 pm


M.A. Seminar on IR Concepts & Theories

The syllabus for my M.A.-level seminar on “IR: Concepts and Theories” is ready and can be found here. Here’s a quick course description:

This course aims at providing students in the M.A. program in Global Affairs with the conceptual and theo-retical toolkit necessary to make informed decisions and recommendations in the realm of international politics. Decisionmakers necessarily use concepts and theories. Often, however, these remain implicit or unconscious, making it harder to detect inconsistencies and other problems with their rationales, and thus negatively impacting the odds of success of whatever course of action is being recommended or implemented. It is the purpose of the course to give students the tools needed to identify, label, evaluate, criticize, and fine-tune policy positions on international topics, allowing them to make better arguments throughout their professional lives.

To do so, the first part of the course is devoted to surveying IR theory, its central questions, approaches, concepts, and theories. Then, in the second half of the course, we will look at several central topics in con-temporary international relations — the causes of war, deterrence and brinksmanship, the spread of nuclear weapons, the transformation of the international system, the diffusion of international norms, and environ-mental politics — through the theoretical lenses we have studied in the first half. This means you should expect to do quite a bit of pushing before you can actually jump in and enjoy the ride. Intellectual effort will be front-loaded, but the rewards should be apparent in the second half of the semester.

Please be aware that the course is not focused on a description or analysis of the events, actors, institutions, or processes which make up contemporary international relations. Nor is the purpose of this course to ex-pose you to cutting-edge academic work in IR. The readings will instead focus on the key conceptual and theoretical tools used in the study of international relations, some of which are a few decades old.

categories: IR theory, teaching. | tags: .

Posted at 6:47 pm


Lecture on the Balance of Power: New Syllabus

This Spring 2014 semester, I am teaching my lecture on “The Balance of Power: Theory and Practice” here at Yale. Here is the slightly revised syllabus.

If you are a student considering whether to take it now or later, please note that I won’t be teaching it again for sure before the Spring 2017 semester.

categories: IR theory, national security, teaching. | tags: .

Posted at 3:58 pm


“Known Unknowns” available online

My article (co-authored with Alex Debs) “Known Unknowns: Power Shifts, Uncertainty, and War,” is now available on FirstView over at International Organization. Here’s the abstract again:

Large and rapid power shifts resulting from exogenous economic growth are considered sufficient to cause preventive wars. Yet most large and rapid shifts result from endogenous military investments. We show that when the investment decision is perfectly transparent, peace prevails. Large and rapid power shifts are deterred through the threat of a preventive war. When investments remain undetected, however, states may be tempted to introduce power shifts as a fait accompli. Knowing this, their adversaries may strike preventively even without conclusive evidence of militarization. In fact, the more effective preventive wars are, the more likely they will be launched against states that are not militarizing. Our argument emphasizes the role of imperfect information as a cause of war. It also explains why powerful states may attack weaker targets even with ambiguous evidence of their militarization. We illustrate our theory through an account of the 2003 US-led invasion of Iraq.

Read the whole thing here.

categories: IR theory, publications, research, war. | tags: , , .

Posted at 10:34 am


Theory of Unipolar Politics

Cambridge University Press has agreed to publish my book Theory of Unipolar Politics. It will be in out in 2014. You can read a précis of the book here.

categories: books, IR theory, national security, publications, research. | tags: .

Posted at 5:25 pm


Summer 2013 course on “U.S. Strategy after the Cold War”

The syllabus for my summer 2013 course on “U.S. Strategy after the Cold War” is ready. You can find a copy here.

categories: national security, teaching. | tags: , .

Posted at 6:05 pm


Symposium on Jervis’s System Effects

The latest issue of the Critical Review features a symposium on the fifteenth anniversary of Robert Jervis’s System Effects. I have contributed a piece titled “We Can Never Study Merely One Thing: Reflections on Systems Thinking and IR.” Here is the abstract:

Robert Jervis’s System Effects was published just as systems thinking began to decline among political scientists, who were adopting increasingly strict standards of causal identification, privileging experimental and large-N studies. Many politically consequential system effects are not amenable to research designs that meet these standards, yet they must nonetheless be studied if the most important questions of international politics are to be answered. For example, if nuclear weapons are considered in light of their effect on the international system as a whole, it becomes clear that they have obviated the need for a global balance of power by allowing states to counterbalance threats by acquiring nuclear weapons rather than investing in massive conventional balancing efforts. Similarly, systems thinking should inform our understanding of the impact of a ‘‘unipolar power’’ such as the United States, which has enjoyed an overwhelming preponderance of conventional military power since the fall of the Berlin Wall. A unipolar power is likely to become involved in frequent conflicts because it is not restrained by the presence of a peer competitor.

You can read the entire piece here.

The remaining pieces in the symposium (by Jeffrey Friedman; Andrea Jones-Rooy and Scott Page; Richard Posner; Philip Tetlock, Michael Horowitz and Richard Herrmann; and Robert Jervis himself) are available here (gated).

categories: IR theory, philosophy, publications, research. | tags: , , .

Posted at 8:42 am


Wohlforth Reviews “Unrest Assured”

William C. Wohlforth has written a review of my article “Unrest Assured,” which came out in International Security (Winter 2011/12), for the ISSF series over at H-Diplo. You can read his review here.

categories: IR theory, national security, nuclear weapons, publications, research, war. | tags: , .

Posted at 10:02 am


When Do Power Shifts Lead to War?

My article “Known Unknowns: Power Shifts, Uncertainty, and War,” (co-authored with Alexandre Debs) is now officially forthcoming in International Organization. Here is the abstract:

Large and rapid power shifts resulting from exogenous economic growth are considered sufficient to cause preventive wars. Such power shifts are rare, however. Most large and rapid shifts result from endogenous military investments. In this case, preventive war requires uncertainty about a state’s investment decision. When this decision is perfectly transparent, peace always prevails. A state’s investment that would produce a large and rapid power shift would prompt its adversaries to launch a preventive war. Internalizing this, the state is deterred from investing. When investments may remain undetected, however, states may be tempted to introduce large and rapid shifts in military power as a fait accompli. Knowing this, their adversaries may strike preventively even without unambiguous evidence about militarization. In fact, the more effective preventive wars are, the more likely they will be launched against states that are not militarizing. Our argument restricts the role of commitment problems and emphasizes the role of imperfect information as causes of war. It also provides an account of why powerful states may attack weaker targets suspected of military investments even in the absence of conclusive information. We illustrate our theory through an account of the 2003 U.S.-led invasion of Iraq.

categories: IR theory, publications, research, war. | tags: , .

Posted at 2:12 pm