This book interprets how ideas of war and peace have functioned as frames of reference within the history of Western political philosophy. Its purposes are both theoretical and practical. These seeming alternatives inform a broad spectrum of political thought, contextualizing the questions we ask about politics, the descriptions of the pragmatic and moral choices we face, and the concepts and metaphors we employ. Beyond theory, this inquiry responds to practical challenges confronting democratic citizens in the twenty-first century. The book’s central claim is that the persistence of both war and peace must be acknowledged as framing conditions for a political philosophy capable of informing the critical judgments that citizens need to exercise, particularly in times of intense regime stress or disturbing human precarity. The author presents five thematic chapters that examine how these alternative perspectives have functioned within some of Western political theory’s most significant works.