Hiroshima and Nagasaki as models of city diplomacy

Mayors worldwide are currently actively engaged in transnationally coordinated efforts to address climate change, pandemics, terrorism, and other global challenges, and a significant amount of scholarly attention has been paid to this development in the fields of international relations, urban studies, and security studies. Yet, curiously, the pioneering work of the mayors of Hiroshima and Nagasaki in their Mayors for Peace campaign and other related efforts to promote a vision of a world without nuclear weapons since the 1970s has scarcely been examined in city diplomacy research. Drawing largely on archival research in Hiroshima and Nagasaki, this article addresses one of the key issues in the field—the legitimacy of city diplomacy. How do mayors justify the use of the limited resources at their city hall’s disposal for a global campaign associated with a policy goal that is beyond their jurisdiction? In the defense and security fields, where national leaders are the primary policymakers and deciders, this question of legitimacy is especially acute. The cases of Hiroshima and Nagasaki’s city diplomacy for the elimination of nuclear weapons are no exception, despite the fact that their legitimacy has often been taken for granted given the two cities’ unique historical experience. The mayors of Hiroshima and Nagasaki have consistently, and at times jointly and at times separately, sought to establish their legitimacy locally, nationally, and internationally. Their city diplomacy since the 1970s has successively revealed several different registers of legitimacy. Each register of legitimacy—enacted through cooperation with the national government; confrontation with the national government; and collaboration with cities, nongovernmental organizations, and individuals outside Japan, respectively—is relational and has entailed distinctively spatiotemporal reconfigurations. While city diplomacy researchers have persuasively argued that the emergence of city diplomacy is emblematic of the structural transformation of the world order in which actors and issues are not simply local, national, or global, the cases of Hiroshima and Nagasaki’s city diplomacy serve as a reminder that the legitimacy of city diplomacy demands consistent relational recalibration through which the current world order is reimagined.