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.

目前，世界各地的市长都在积极参与跨国协调的工作，以应对气候变化，大流行，恐怖主义和其他全球性挑战，并且在国际关系，城市研究和安全研究等领域，这种发展得到了学术界的广泛关注。 。然而，令人奇怪的是，自1970年代以来，广岛市长崎市长崎市长和市长崎市市长市市长在开展和平市长运动等方面的开创性工作和其他有关努力，以促进建立一个没有核武器的世界的构想。本文主要基于广岛和长崎的档案研究，着眼于该领域的关键问题之一-城市外交的合法性。市长如何证明其市政厅可支配的有限资源用于与其管辖范围之外的政策目标相关的全球运动的合理性？在国防和安全领域，国家领导人是主要的决策者和决策者，这个合法性问题尤为突出。尽管广岛和长崎市政府消除核武器的外交案例也不例外，尽管鉴于两座城市独特的历史经验，它们的合法性常常被认为是理所当然的。广岛市长崎市长和市长市长一贯，有时是联合，有时是分开，试图在地方，国家和国际上确立其合法性。自1970年代以来，他们的城市外交已经陆续揭示了几种不同的合法性记录。每个合法性登记册-通过与中央政府合作制定；与中央政府的对抗；与分别与日本以外的城市，非政府组织和个人的合作是关系性的，并且需要进行独特的时空重构。尽管城市外交研究人员有说服力地指出，城市外交的出现象征着世界秩序的结构转变，在这种世界秩序中，行动者和问题不仅是本地，国家或全球的，广岛和长崎的城市外交案例也提醒我们城市外交的合法性要求对关系进行重新调整，从而重新构想当前的世界秩序。与中央政府的对抗；与分别与日本以外的城市，非政府组织和个人的合作是关系性的，并且需要进行独特的时空重构。尽管城市外交研究人员有说服力地指出，城市外交的出现象征着世界秩序的结构转变，在这种世界秩序中，行动者和问题不仅是本地，国家或全球的，广岛和长崎的城市外交案例也提醒我们城市外交的合法性要求对关系进行重新调整，从而重新构想当前的世界秩序。与中央政府的对抗；与分别与日本以外的城市，非政府组织和个人的合作是关系性的，并且需要进行独特的时空重构。尽管城市外交研究人员有说服力地指出，城市外交的出现象征着世界秩序的结构转变，在这种世界秩序中，行动者和问题不仅是本地，国家或全球的，广岛和长崎的城市外交案例也提醒我们城市外交的合法性要求对关系进行重新调整，从而重新构想当前的世界秩序。