It could be said that American foreign policy since 1945 has been one long miscue; most international threats - including during the Cold War - have been substantially exaggerated. The result has been agony and bloviation, unnecessary and costly military interventions that have mostly failed. A policy of complacency and appeasement likely would have worked better. In this highly readable book, John Mueller argues with wisdom and wit rather than ideology and hyperbole that aversion to international war has had considerable consequences. There has seldom been significant danger of major war. Nuclear weapons, international institutions, and America's super power role have been substantially irrelevant; post-Cold War policy has been animated more by vast proclamation and half-vast execution than by the appeals of liberal hegemony; and post-9/11 concerns about international terrorism and nuclear proliferation have been overwrought and often destructive. Meanwhile, threats from Russia, China, Iran, and North Korea, or from cyber technology are limited and manageable. Unlikely to charm Washington, Mueller explains how, when international war is in decline, complacency and appeasement become viable diplomatic devices and a large military is scarcely required.