It is a commonplace to observe that the study of international relations is strongly driven by current events. So what implications do the events of September 11 2001, and their aftermath, have for the way in which International Relations is studied? Is September 11 a transformative event, like the Second World War, or something less, such as the Cuba missiles crisis? In particular, how does September 11 affect the claims of mainstream IR theories, and the balance of power among them? This paper reviews the claims of neorealism, globalism, regionalism and constructivism, taking them together as a set of partial truths that collectively constitute the framework of debate about international relations. It argues that each line of theory can and has claimed relevance in explaining September 11 and its aftermath, and that these claims are by and large valid. It concludes that no mainstream theory has been invalidated, that no new theory is needed to fill gaps exposed by September 11, and that neither the balance of claims nor the nature of the tensions amongst these theories has been changed. This is not to argue a case for complacency about the state of IR theory in general. Like the Cuba missiles crisis, September 11 does suggest that a focus on the internal processes of foreign policy making in the US will be particularly important.
International Relations; Theory; September 11; Neorealism; Globalism; Regionalism; Constructivism