America's quagmire in Vietnam, France's preoccupation with overseas empire, Japan's attack on the United States, Germany's aggression in Europe, Britain's appeasement of Hitler - what motivated these bouts of self-defeating behavior? According to Charles A. Kupchan, all of these episodes are rooted in a common strategic logic.

Building on extensive archival research, Kupchan offers a bold new explanation for the rise and fall of modern empires, focusing on the extremist policies that contribute to their demise.

Kupchan provides detailed accounts of the imperial careers of Britain, France, Japan, Germany, and the United States. At times, he shows, each of these states responded to changes in the international distribution of power by pursuing reasoned strategies that enhanced its prosperity and security. At other times, however, they all engaged in bouts of self-defeating extremism. Kupchan argues that it was their perception of national vulnerability that drove them to such behavior.

When a state lacks the resources to cope with prospective adversaries, decision makers justifiably adopt extremist policies. In order to gain domestic support for these policies, they sell to the polity conceptions and images of empire which alter strategic culture - public attitudes, the mindset of top elites, and the organizational interests of elite institutions.

Decision makers later find, however, that they are entrapped in a strategic culture of their own making, unable to reorient grand strategy and avoid self-defeating behavior. The Vulnerability of Empire will be crucial reading for political scientists, international relations specialists, modern historians, and policy makers.