Steven Pinker's The Better Angels of Our Nature is, quite simply, one of the most influential social science books of the past decade. In it, Pinker argued that violence in all its forms-but especially war-has been steadily declining throughout the modern era, and that the world is more peaceful now than ever before. The book found a very receptive audience, and it is indeed a powerful work. But is it true? In Only the Dead, Bear Braumoeller assesses the claim that armed conflict is in decline and finds it wanting. In the course of his assessment, he also develops a powerful explanation for trends in warfare over time. His central finding is that, although there has been a drop in the rate of international conflict following the end of the Cold War, that drop followed nearly two centuries of steady increases in the rate of conflict. Moreover, the rate of civil war onset has increased following the end of the Cold War, and extrastate wars (wars between states and non-state entities) have shown a recent resurgence. With regard to war intensity and severity, he has found no significant change since the end of the Napoleonic Wars-which represents a sharp rejoinder to Pinker's thesis. Just as importantly, he contends that the flaws in Pinker's argument flow from a fundamental weakness in this theory, which is really a monocausal story about a decline in the willingness to wage war. In contrast, Braumoeller's findings are in accord with systemic theories of international politics that emphasize Great Power conflict. He therefore traces how Great Power interactions produce world orders, which in combination with Great Power activity alter the calculations made by states as they contemplate the choice between a negotiated settlement and war. To buttress his argument, he looks at key episodes from each major historical era, all the while emphasizing how the Great Power system induces armed conflict. Because the decline-in-war thesis has captured the attention of politicians, journalists, and citizens as well as academics, Only the Dead is likely to be quite controversial. But Braumoeller, known for being one of the most numerate political scientists in the discipline, has both a powerful theory and data that doubters cannot dismiss. It therefore has the potential to stand as a landmark work in the fields of international politics and the history of war.