Central to China’s identity, drugs have been inextricably linked to every aspect of the country’s economy, polity, society, and culture since the early nineteenth century. This book is the first comprehensive study of anti-drug crusades in twentieth-century China. Zhou Yongming addresses the complexity of anti-drug campaigns by examining how modern Chinese nationalism and the needs of state building have shaped the ways in which these campaigns have been carried out. The author traces the important role that nationalism has played in all of China’s anti-drug crusades by providing the motivation, legitimacy, and emotional charge needed for Chinese authorities to take an anti-drug stance. Nationalism has provided a forum for fashioning mainstream anti-drug discourse, interpreting the history of the Opium Wars, and mobilizing the social elite and general public in the cause of drug suppression. Yet to avoid adopting nationalism as a universal concept, the author argues that its complexity and mutability can only be fully appreciated if its multiple forms and meanings in modern China are explored. At the same time, the author contends that anti-drug campaigns also are closely related to internal politics. He shows that both the Nationalists and the Communists used these campaigns to build state hegemony through mass crusades, nationwide mobilization, and the use of state violence. To achieve its goal, the state often adopted multiple interpretations of the nationalist anti-drug debate and then incorporated them into the state’s hidden agenda of conducting anti-drug campaigns. Drawing on previously unavailable archival sources and personal interviews, the author tells a rich story that will be valuable to Asia scholars and narcotics researchers alike.