The evolving role of cities in international affairs is increasingly apparent, with municipal governments stepping into areas traditionally reserved for national diplomacy. This trend, often referred to as city diplomacy, urban diplomacy, local diplomacy, or subnational diplomacy, is gaining momentum as cities grapple with global challenges and seek to forge their own paths on the world stage. Recent initiatives by cities like Yokohama, Japan, and Taipei, Taiwan, illustrate the diverse approaches and growing sophistication of this phenomenon.
Experts estimate that by , approximately 68% of the world’s population will reside in urban areas, making cities central to addressing issues like climate change, economic inequality, and security. As national-level diplomacy sometimes falters, cities are finding ways to fill the gaps in global governance and advocacy. This shift is reflected in the growing body of academic research dedicated to understanding city-level international engagement.
Yokohama, a major port city south of Tokyo with a population of over 3.5 million, exemplifies a strategic approach to city diplomacy. The city’s international engagement, rooted in its history as a trading hub following the Meiji Restoration in the mid-19th century, encompasses technical cooperation, activism on global issues, and sister city relationships. A key element of Yokohama’s strategy is its publicly available “International Strategy” pamphlet, outlining objectives to foster an inclusive society, grow its economy, and address global challenges.
Yokohama actively participates in international organizations like C40 Cities, winning an award in for its Yokohama Smart City Project, a collaborative effort with 34 Japanese companies focused on energy efficiency and decarbonization. The city also holds the designation of a UN Peace Messenger City and participates in the Mayors for Peace organization, promoting its peace-making aspirations. The Y-Port Program, a public-private partnership launched in , facilitates collaboration with cities across Asia to address environmental problems related to urban development.
Yokohama maintains eight sister cities and seven partner cities, many established between and . Its commitment to international cooperation was recently demonstrated through its support for Odesa, Ukraine, following the Russian invasion. In , the mayor of Odesa visited Yokohama, leading to a Memorandum of Understanding on sustainable urban development and a commitment from Yokohama to provide humanitarian aid and assist with infrastructure rebuilding.
Taipei, the capital of Taiwan, also presents a compelling case study in city diplomacy. A primary focus of Taipei’s international engagement is to overcome Taiwan’s political isolation, a motivation often evident in the activism of Taipei’s mayor in international forums. The city actively promotes its cultural heritage, demonstrates expertise in sustainable development and smart city technology, and expands its network of sister cities.
Taipei’s involvement in city networks, such as the United Cities and Local Governments, Asia-Pacific Branch (UCLG-ASPAC), and its participation in events like the Smart City Summit & Expo, contribute to its global visibility. The city has also established the Global Organization of Smart Cities (GO SMART), boasting over 2,000 members worldwide. The Songshan Cultural and Creative Park, a repurposed former tobacco factory, serves as a showcase for creative industries and a platform for international cultural exchange.
With 53 sister cities, three partner cities, and five friendship cities, Taipei has cultivated a broad international network. These relationships, formalized between and , aim to foster education, cultural exchange, business investment, and the sharing of urban development expertise, ultimately enhancing Taiwan’s visibility on the global stage.
Both Yokohama and Taipei demonstrate a maturing approach to city diplomacy, emphasizing sustainable urban development and technology. While Yokohama focuses on technical cooperation and expertise-driven solutions, Taipei prioritizes political visibility and cultural exchange. These distinct yet complementary models highlight the diverse ways cities can act as international actors, advancing local interests and shaping global discourse.
The professionalization of city diplomacy is evident in the work of organizations like C40’s Knowledge Hub, the City Diplomacy Lab, and the Melbourne Centre for Cities, all striving to improve practices and share best practices. This trend is also reflected in the increasing number of academic publications dedicated to the subject. As state-level diplomacy faces challenges, the efforts of cities and other subnational actors offer a potential pathway toward more effective global cooperation. Recent examples, such as New York City joining the WHO’s Global Outbreak Alert and Response Network after the US withdrawal, demonstrate a willingness to circumvent national-level deficiencies and address global problems directly. While not a complete solution, the proactive engagement of cities provides a reason for cautious optimism in an increasingly complex world.
