Never at War: Why Democracies Will Not Fight One Another is a book by the historian and physicist Spencer R. Weart published by Yale University Press in 1998. It examines political and military conflicts throughout human history and finds no exception to one of the claims that is made by the controversial democratic peace theory that well-established liberal democracies have never made war on one another. In addition to the democratic peace, Weart argues that there is also an oligarchic peace and provides a new explanation for both the democratic and oligarchic peace. The book is often mentioned in the academic debate and has received both praise and criticism.