This is an intriguing little book. When, Dudziak asks, does “wartime” begin and end? Even in the case of wars that seem to have clear beginnings and endings, such as the two world wars, it turns out that there is fuzziness at both ends. Indeed, Dudziak notes that to judge from the campaign medals awarded to members of the U.S. armed forces for service in military operations, there barely seems to have been any time in “postwar” American history that was not, in some sense, wartime. In democratic countries, war is assumed to be an exceptional condition that makes it acceptable for governments to suspend normal rights and liberties. But the “war on terror” suggested how that process could become interminable. This is a thoughtful and original take on the concept of war. But it is less convincing as an explanation for the application of exceptional measures. Successive British governments, for example, insisted that there was no war in Northern Ireland but nevertheless enacted far-reaching antiterrorist legislation.