This paper traces the history of modern terrorism from the end of the Second World War to the beginning of the twenty-first century. It divides that history into three stylized waves: terrorism in the service of national liberation and ethnic separatism, left-wing terrorism, and Islamist terrorism. Adopting a constitutional political economy perspective, the paper argues that terrorism is rooted in the artificial nation-states created during the interwar period and suggests solutions grounded in liberal federalist constitutions and, perhaps, new political maps for the Middle East, Central Asia and other contemporary terrorist homelands.