Entering a New Phase of Geopolitical De-Risking

Entering a new phase of geopolitical de-risking. Sister city partnerships in the U.S. as gateways of Chinese influence

A new phase for city diplomacy

After World War II, U.S. President Eisenhower (1953 to 1961) initially started sponsoring sister city agreements. In 1956, the White House Conference on Citizen Diplomacy marked the capstone of local people-to-people diplomacy, laying a foundation for pursuing world peace (Sister Cities International, 2025). Formal, long-term cooperations between municipalities and provinces of different nations, negotiated by their official representatives, became an established instrument in the external relations of cities (Acuto et al, 2018). Currently, there are around 286 Sino-U.S. sister city partnerships (Belt and Road Portal, 2024) concerned with projects of U.S. companies in China, Chinese investments in the U.S., and various cultural, educational and professional people-to-people exchanges and cooperations.

As U.S.-China great power competition resurges in areas of global trade, new and emerging technology, hydride defense and global infrastructure, times have dramatically changed (CFR, 2025). Sister-city relationships between the U.S. and its major antagonist on the global stage are no longer framed as initiates that are promoting understanding between nations but as gateways of influence. A former U.S. Secretary of State warned, “China is aggressively attempting to influence state and local governments, including through seemingly innocuous sister-city agreements” (AP, 2020). Traditionally apolitical sister-city agreements turned into a bone of contention. The right approach is vigorously discussed as the case of the Washington Sister Cities Act (2025) demonstrates. In 1984, Washington D.C. officially became Beijing's sister city. More than forty years later, a range of concerns spur a debate on whether U.S. cities should generally suspend Sino-U.S. city agreements. Several legislators around Rep. Moolenaar (R-MI-2) called the Mayor of Washington D.C. Bowser (D-DC) to review and to end the sister city arrangement. The initiative intents to terminate and to prohibit municipalities in the District of Columbia from entering city sister relationships with foreign adversaries (U.S. Congress, 2025).

The asymmetry between the authoritarian Chinese system and the lax U.S. framework for city diplomacy is associated with underestimated vulnerabilities of U.S. national security. Key element to closing those vulnerabilities include enhanced tactical alignment on activities that cities engage in, strategic coherence, operational coordination and tactical alignment of city diplomacy with national security priorities. In the worst case, U.S. cities send out conflicting signals, create risks for concerned parties and expose unprotected entry points to foreign influence. This article thus examines how U.S. cities can navigate geopolitical derisking and close vulnerabilities related to Sino-U.S. sister city partnerships.

Cities in a heterarchical world

The burgeoning academic subfield of city diplomacy spans the research areas of International Relations and urban studies (Amiri & Sevin, 2020; Marchetti, 2021). Modern city diplomacy is a phenomenon of a plural and heterarchical international political system in transition. As there are frequent multilateral interactions between global cities, national governments and non-governmental actors (Acuto, 2013), city diplomacy can be understood as a facete of pluralism of global entities (Cornago, 2010). Urban diplomacy resonates with a world order in which national government no longer solely determine the rules. City governments therefore pursue to assume policy arenas that traditionally are national domains (Koehn & Rosenau, 2002). Examples are local aspects of migration management, technology policy, resilience building, democratic renewal, environmental and climate action. Also, city diplomacy resonates with a world order described as heterarchical. Heterarchy is a global governance system with overlapping hierarchies and each respective governing principles (Cerny, 2023). For example, after the U.S. federal government announced its withdrawal from the Paris Agreement in 2017, cities like New York, Chicago, and Los Angeles stepped up their pragmatic efforts to claim the lead. 294 U.S. cities and counties voluntarily recommitted to uphold the targets through the “We Are Still In” (2025) initiative.

City diplomacy is discussed as a subtype of paradiplomacy, an acronym for parallel diplomacy (Butler, 1962). It encompasses activities of either “supporting, complementing, correcting, duplicating, or challenging the nation-states’ diplomacy” (Soldatos 1990, p. 17) and mostly operates “through permanent or ad hoc contacts with foreign public or private entities, with the aim of promoting socioeconomic or cultural issues” (Cornago 1999, p. 40). Cities engage with global affairs “with the aim of representing themselves and their interests” (Van der Plujim, 2007, p. 6). In their capacity as diplomatic players (Tavares, 2016), cities have multi-scalar agency, meaning their representatives have ties across all governmental levels. Parallel to nation states that conduct relations by official agents and peaceful means, cities facilitate communication, negotiate bilaterial agreements, and symbolise the existence of an international society (Bull, 1995). To this end, cities send delegations, open foreign offices, and organise business missions, partly mimicking national diplomacy. Second, cities are credible trust-brokers for interests of local communities, e.g., infrastructure projects, innovation ecosystems and sustainable development. Third, cities deliver on their mandate by leveraging their unique Non-Governmental Organisations (NGO)-like agility through global alliance building. Cities establish organisations under private law, such as global city networks (Acuto, 2013; Bouteligier, 2012).

A world of difference

There's a world of difference between PRC and U.S. city diplomacy approaches. Considering different political regimes and modes of inter-agency coordination, Chinese city diplomacy is aligned with national objectives, while in the U.S. representative democracy cities claim self-governance. Local leaders in the U.S. act relatively autonomous and serve their mandate independently from national politics (Bursens & Deforche, 2010). The federal system allows sub-national governments a room for maneuver to pursue local interests, regardless of the capital´s concerns (Hoover Institution, 2018). The role of the U.S. Department of State (DOS) in urban diplomacy has been historically weak and limited.

In contrast, in the PRC, a centralised authoritarian system with a vertically integrated governance, cities operate under tight Chinese Communist Party (CCP) control. The PRC´s policy is to “use sister city relations to expand China´s economic agenda separate to a given nation´s foreign policy.” (Brady, 2017, p. 9). An arrangement of different entities determines how China's cities engage with U.S. counterparts. The United Front Work Department (UFWD) and the Chinese People’s Association for Friendship with Foreign Countries (CPAFFC) are in charge of cultural and social outreach abroad through China's influence campaigns (De La Bruyere & Picarsic, 2021; De La Bruyère, 2023; Toi-Yeung & Möller, 2024). The CPAFFC is supposed to oversee sister people-to-people, city-city and enterprise-to-foreign-enterprise activities to execute China's global agenda (Lulu, 2019). According to the U.S. Department of State, the CPAFFC “has sought to directly and malignly influence state and local leaders to promote the PRC’s global agenda” (DOS, 2020). The CPAFFC is subordinate to the UNFWD. Sister-city agreements must be approved by the Chinese Foreign Ministry (Yan, 2023). CPAFFC “officials build personal relationships than can then be ´weaponized´ when a city plans an activity the CCP does not like” (Hamilton & Ohlberg, 2020, p. 91). Relevant political issues for China are the protest and massacre on the Tiananmen Square 1989, the autonomy of Hong Kong, the independence of Tibet, the status of Taiwan, or human rights conditions in the People's Republic of China (PRC), e.g. genocidal policies against ethnic minorities. Chinese city diplomacy is thus understood as an extension of Chinese interests and geostrategic power (Xiong & Wang, 2013; Zhao & Chen, 2013). In stark contrast to the U.S., there is inter-agency coordination of city diplomacy action in place and interactions are under tight control.

From a comparative perspective, U.S. city diplomacy takes place in bottom-up, city-to-city partnership driven by local needs. Local officials can take decisions without interference by federal authorities. In contrast, China pursues a top-down, whole-of-government approach, embedded in national strategy. Chinese city diplomacy is strategically aligned and politically subordinate to the ostensibly all-powerful CCP national foreign policy objectives. However, Chinese cities usually maintain divers and substantial subnational cooperation over a long time as long as they serve and follow Beijing’s foreign policy lead.

Global expansion of partnerships

Over time, Chinese sister city partnerships created an ever-denser global network. The first Chinese sister-city partnership was established between Beijing and Tokyo, Japan, in 1979. China's economic opening through the Deng Xiaoping's 1978 reforms built trust and prosperity through commercial cooperation as a bulwark of better Sino-U.S. relations. In the 1990s and 2000s opportunities for economic cooperation in the Global East became more relevant for the PRC. After the financial crisis of 2008 until 2019, there was a witnessed rapid expansion of partnerships with developing countries (Xu, Liu & Huang, 2023) (see Figure 1). In particular, cities with industrial relevance for global supply chains and logistics infrastructure are of profound interest. City diplomacy is at the focus of China's geopolitical outreach and thus a powerful indicator to trace the People´s Republic´s global ambitions.

1978 and 1980s

1990s and 2000s

2010s and 2020s

Opening policy and

economic growth

Economic cooperation between countries in the Global East

Strengthening global influence and outreach

Figure 1: Evolution of Chinese transnational city partnerships

(Source: Xu, Liu & Huang. 2023).

The total number of sister relationships differ, depending on the source. Most sources refer to a number around 286 pairs of sister relationship between the U.S. cities and counties and Chinese counterparts (Belt and Road Portal, 2024). By 2019, roughly 2,600 Chinese municipalities had foreign sister cities or provinces all around the globe, including about 200 in the U.S. and 700 in Europe (Gottlieb, 2023). According to People’s Daily, since the mid-1950s China has even established over 2,900 pairs of sister cities with more than 140 countries (Gering, 2025). The resource endowment of cities within the Sino-North American sister city network are a significant factor for the development of sister city partnerships (Wu, Li & Hu, 2018). Long-term and reliable city-to-city relations across the Pacific are established between, e.g. San Francisco and Shanghai (1979), Seattle-Chongqing (1983), Orlando-Guilin (1986) and Houston-Shenzhen (1986). The U.S. states with the most sister partnerships with cities in the entire Indo-Pacific region are California (245), followed at some distance, by Washington (73), Texas (47), Florida (33), Oregon (38) and Indiana (35) (Asia Matters for America/America Matters for Asia, 2022).

Gateways of Chinese influence

Literature on derisking of city diplomacy addresses risks that can be understood as “vulnerabilities to local development obstacles, damages, and biases stemming from a subnational government´s international activities” (Grandi & Sottilotta, 2024, p. 3). More precisely, geopolitical risks are arising from cities´ exposure to geopolitical shifts and power dynamics in international relations (Grandi & Sottilotta, 2025; Campisi et al., 2025). As U.S.-China great power competition resurges, the era of naïve global engagement is over. The operative environment of city diplomats is “the front lines of national security [as] leaders at the U.S. state, local, tribal, and territorial levels risk being manipulated to support hidden PRC agendas. PRC influence operations can be deceptive and coercive” (National Counterintelligence and Security Center, 2022, p.1). Three vulnerabilities of adverse urban diplomacy stand out, namely investments into critical infrastructure, infiltration by illegal agents and influence of subsidiary entities. As the National Counterintelligence and Security Center indicates, Chinas official goals can diverge from covered goals (NCSC, 2022). This threat vector matrix illustrates which covered adverse policy goals are associated with different areas of city-to-city engagement (see Figure 2).

Threat vectors

Areas of engagement

Covered adverse goals

Investments into

urban critical infrastructure

Economic cooperation

Co-ownership of major infrastructures,

industrial espionage,

intellectual property (IP) theft

Infiltration by

illegal foreign agents

Hidden

political activities

Information acquisition,

interference into democratic

decision-making processes

Influence of foreign subsidiary entities

Cultural and social cooperation

Influence on public opinion through disinformation and propaganda

Controlling and policing the diaspora

Figure 2: Threat vectors, areas of engagement and goals of adverse city diplomacy

(source: Own compilation).

The threat vectors related to adverse city diplomacy shall be illustrated with cases from the State of California. First, sister city relationships can enhance a city's attractiveness to foreign investors and can have long-term, positive effect on Chinese outward foreign direct investment (Han, 2020; He, Tang & Wei, 2025). However, adverse city diplomacy can open gateways for co-ownership of critical infrastructures. One case for short-sighted local decisions on critical infrastructure investments is the Long Beach container terminal. After national-security review of the Chinese shipping cooperation´s interests in the terminal, U.S. authorities required divestiture because of national security concerns (OOCL, 2019). Second, sister city relationships can foster close political relations between local elites and communities, but they can also provide open backdoors for infiltration by illegal foreign agents or the recruitment of political staff as proxies for political advocacy (DHS, 2020). For example, in the City of Arcadia, Los Angeles County, a Chinese illegal agent of the PRC tried to manipulate an election and reported to Chinese officials about how to influence local US politicians (U.S. Attorney’s Office, 2025).

Also, sister city relationships can create bias that make local leaders careless against threats related to foreign subsidiary entities. They can be platforms for influence campaigns on public opinion through disinformation and propaganda and abet controlling and policing of overseas communities. A case of manipulation of public opinion through disinformation and social control happened during the Chinese President's visit of the Asia-Pacific Economic Cooperation conference. In San Francisco pro‐CCP diaspora groups, possibly linked to Chinese consular officials, were accused of organising demonstrators to counter Tibet and pro‐Taiwan protesters (Washington Post, 2024). This case shows how China's extraterritorial reach in the U.S. can materialise in social discourse framing (Wong, 2022). While the number of Confucius Institutes in the U.S. dramatically collapsed between 2019 and 2024 (U.S. GAO, 2023), other problematic foreign subsidiary entities are still locally involved in the U.S. Considering an engagement of Californian representatives with the CPAFFC, e.g. in the Bay-to-Bay Dialogue, higher awareness of PRC's strategic operations to exploit unfair advantages is urgency needed (CSIS, 2023).

Multi-level diplomacy framework

An U.S. multi-level diplomacy framework is evolving gradually. In 1979, the State Department created an Ambassador-at-Large for Liaison with State and Local Government, but since then, similar functions concerned with city diplomacy have been temporary stand-alone offices. A remarkable legislative step forward was introduced by Rep. Lieu (D-CA-33) and Rep. Wilson (R-SC-2) in 2019. The City and State Diplomacy Act (2019) created an office of subnational diplomacy within the U.S. Department of State. Rep. Lieu argues the act helps us push back global competitors by giving local leaders the tools needed to navigate foreign pressure and exploitation. Federal support could leverage the expertise, talent, and energy of local and regional officials (Lieu, 2022). Also, since 2019, the State Department has required Chinese diplomats seeking to meet with state and local leaders in the U.S. to notify it in advance (New York Times, 2019). In 2020, Sen. Chris Murphy (D-Conn) and then-Senator David Perdue (R-GA) introduced the City and State Diplomacy Act (2020) in the Senate. The legislative proposal has received bipartisan support and found its way into the House’s Defense Authorization Act for Fiscal Year 2022.

In the last years, de-risking approach shaped the legislation on city diplomacy. Since 2020, the Special Representative for City and State Diplomacy offers customised China briefings to governors’ and mayors’ offices that request them, enabling the Department of State to fill Chinese influence analysis, and strategies for counteraction (DOS, n.d.). In 2024 the US House of Representatives hold the so-called China week with 25 bills related to technology and trade-related risks, countermeasures against economic espionage, and restrictions on Confucius Institutes (Morgan Lewis, 2024). On state level, in 2024 Indiana introduced provision prohibiting local governments from entering into sister-city agreements with units located in states designated a foreign adversary (Indiana House of Representatives Bill 1120, 2024). In 2025, the Arkansas “Communist China Defense” package and the Texas Government Code restrict establishing sister-city relationships with prohibited foreign parties (Arkansas House of Representatives Bill 1352, 2025; Texas House of Representatives Bill TX HB128, 2025).

Geopolitical derisking

The current U.S. city diplomacy polity framework is ill-equipped to execute geopolitical derisking. In a 2020 survey of 47 global cities by the Chicago Council on Global Affairs, 78 percent of respondents said they would engage more in city diplomacy if they had dedicated funds (Kosovac et. al., 2020). Compared to their counterparts in Western Europe, Japan, and certain cities in Latin America, U.S. city diplomacy units are understaffed. For example, Tokyo and Buenos Aires each employ a 40-person international affairs team focused on city diplomacy, while the largest international affairs offices in the U.S. are in Los Angeles and New York City, each with only 10-12 staffers (Bouchet, 2024). In the U.S. most “state and local governments do not have the capacity to track Beijing’s influence tactics and do full due diligence on what may be involved in economic offers from Chinese companies” (Senate Foreign Relations Committee, 2025, p. 8f.). This can result in administrative overload and under-coverage of foreign threats. In the worst case, cities undermine their immanent interests, engage in dangerous silo thinking, send out conflicting policy signals, create risks for concerned parties and expose unprotected entry points to foreign influence. I thus argue in favour for a new approach to counter geopolitical threats of adverse city diplomacy. Such a multi-level de-risking strategy on city diplomacy would create better strategic coherence, foster operational coordination and enhance tactical alignment.

First, geopolitical de-risking of city diplomacy requires strategic coherence of guiding principles such as transparency, integrity and reciprocity of safe city-to-city relations. Cities should ensure full transparency in dealings with Chinese entities by making agreements public, holding hearings, and applying the same legal standards used for American partnerships. Cities should strengthen integrity by understanding influence operations, staying updated on Washington’s China policies, and consulting federal agencies. However, cities shall avoid short-term and opportunistic engagements, measure impacts of and integrate local demands into international agendas (Acuto et al., 2018). They must also promote beneficial reciprocity of partnerships by tracing the origins of foreign investments, identifying ties to malicious influence networks, and ensuring fair treatment of controversial issues (Hoover, 2018).

Second, geopolitical de-risking of city diplomacy requires operational coordination of knowledge and information capacities. Associations such as the National Conference of Mayors shall strengthen networking activities to share best and worst practice experiences and raise awareness for geopolitical challenges for city diplomacy. Think-tanks, e.g. the Truman Center for National Policy, the Brookings Institution, the RAND Corporation/ USC Center on Public Diplomacy and the Council of Global Affairs shall continue valuable research on risks related to foreign investments and foreign subsidiary entities. Also, an underexploited asset are resources from private security partners and the philanthropic sector.

Third, geopolitical de-risking of city diplomacy requires tactical alignment of multi-level risk management. Grandi & Sottilotta (2025) recommend that an independent national city diplomacy office shall provide consultation, monitor threats, and support risk assessments of city administrations. This would “empower U.S. state and local governments to make informed decisions about the PRC.” (…) “Congress should strengthen the Subnational Diplomacy Unit to make its counter-China efforts more robust” (Senate Foreign Relations Committee, 2025, p. 8). The Subnational Diplomacy Unit and the FBI provide briefings and conducted outreach to state and local governments involved in subnational US-Chinese city diplomacy. Moreover, the unit should set clear guidelines for interaction with Chinese counterparts, ensure regular communication and consultations between cities and federal partners (Jaros & Newland, 2025). It should map the extent influence activities, utilise existing city and state diplomacy toolkits, assess and update existing laws on foreign interference and transparency and provide specialised training (Gering, 2025). When assistance for local threat analysis is necessary, U.S. cities should even have the opportunity to go up the chain of command and request prompt briefings from clearance-bearing personnel within the intelligence community. Cities are recommended to communicate initial suspicion of potential foreign influence with U.S. intelligence agencies, including regional fusion centers, local FBI offices and U.S. Department of Homeland Security (NSCS, 2022).

Conclusion

While Chinese city diplomacy is strategically aligned with national objectives, U.S. counterparts have more leeway. For the time being, the U.S. city diplomacy framework is ill-equipped for respective geopolitical derisking on a local level. In times in which city diplomacy is used as a tool for strengthening China´s economic, ideological and cultural influence, vulnerabilities and threats should deserve increased attention. The U.S. should avoid replicating the top-down authoritarian Chinese approach. The U.S. needs a security strategy on city diplomacy that highlights capacity-building and multi-level risk management to prevent influence operations, safeguarding democratic integrity, economic openness and civil liberties of local communities. Key element to closing those vulnerabilities include strategic coherence, operational coordination and tactical alignment. Future research should map vulnerabilities related to transnational sister city partnerships and review local resources and procedures to secure city diplomacy action. It shall be discussed how transparency, accountability and integrity standards can be calibrated without local administrative overload or disproportionate national control.

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