Only the Dead is the most comprehensive mixed-methods analysis to date of an old and important debate that Stephen Pinker’s (2012) Better Angels and learned – if colorful – responses to it (Cirillo and Taleb 2016) have brought to a popular audience in the last decade. While it is a work of outstanding social science by an eminent scholar of international security and war, Only the Dead is also accessible to this same popular audience, and makes a significant contribution to both researchers in his field and broader society. The foremost among those contributions is to identify, with clarity that previous scholars have not, the role of international orders in keeping peace among their members – and driving conflict externally (Braumoeller 2019, p. 5). While others (Freedman 2014, Hoffman 2016) have suggested this, Braumoeller is the first to test the proposition systematically, arguing convincingly that such orders, and not shifts in underlying human views of war or even human nature, shape the likelihood of extreme violence in particular places and times. Doing so is likely to stimulate future research that will increase our understanding of war, peace, conflict and cooperation.