Principles of Modern City Diplomacy and the Expanding Role of Cities in Foreign Policy

Modern city diplomacy finds city governments intervening in nearly all foreign policy arenas traditionally managed by nation-states. These trends are explicable by the same factors shaping the “municipal foreign policy” movement during the Cold War, while also growing more complex. In this study, I discuss four factors as they shape current city diplomacy trends. I also discuss their theoretical and policy implications. First, cities intervene to enforce universal norms when the national government violates or fails to enforce them, as seen in global cities recommitting to the Paris Accord in response to the Donald Trump administration’s withdrawal. Second, democratic regimes enable local defiance of national foreign policy, while non-democratic regimes such as China harness a more restricted sort of city diplomacy as an extension of national diplomacy. Third, social movement conditions whereby local officials’ views align with constituents on foreign policy issues enable and constrain city diplomacy activity, as seen in U.S. cities declaring themselves sanctuaries in response to the Trump administration’s immigration policies. Fourth, cities often follow economic growth–seeking interests when overlapping with governance issues, as seen in international urban climate change cooperation aimed at foreign market entry, export promotion, and investment attraction.

Editor's note:

This argument appears in Vol. 74, No. 1, "Global Urbanization: Nations, Cities, and Communities in Transformation" (Fall/Winter 2021).

Benjamin Leffel
January 14, 2022


This study provides a theoretical synthesis that explains present-day trends in city diplomacy, or city government intervention in foreign affairs otherwise managed by the nation-state. In a recent article in the Hague Journal of Diplomacy, I used an initial iteration of this synthesis to explain factors shaping the “municipal foreign policy” movement during the Cold War.[i] The present piece expands upon this synthesis to explain modern and global-scale city diplomacy trends.

This piece is organized as follows: The first section argues that cities intervene to enforce universal norms when their national government violates or fails to enforce them, as illustrated by the bottom-up response to the U.S. withdrawal from the Paris Agreement under the Trump administration. It further explains the norm enforcement function and articulates city diplomacy as a social justice mechanism. The second section uses the example of China to argue that non-democratic regimes commandeer city diplomacy for national foreign policy purposes, unlike their democratic counterparts, and that city networks spread democratic processes beyond the sovereign nation-state. The third section argues that municipal foreign policy implementation requires local official-constituent alignment on foreign policy issues, as seen in the sanctuary movement during the Trump administration. The fourth section argues that economic pursuits are expanding in city diplomacy but risk diminishing returns to social welfare if private actors gain excessive influence. Finally, the study concludes with policy recommendations on models of city diplomacy that cities and nations alike should aim to implement.

Norm Violation and Enforcement

City and state governments often engage in diplomacy as a direct response to national government transgressions in foreign policy, including the violation of universal norms or the failure to sufficiently enforce them.[ii] This can be explained by the sociological tradition of world society theory, which assumes that norms such as human rights diffuse internationally and are implemented by nation-states,[iii] but that subnational authorities may intervene and independently enforce said norms if the nation-state fails to do so.[iv] The common thread with international relations theory is the recognition of an emergent international society affecting and limiting the actions of nation-states, including the moral imperatives of Kantian universalism[v] and the shared knowledge, identities, and norms of constructivism.[vi] The concept of plural diplomacies situates local governments within this international society, which are then prompted to take diplomatic action by a normative desire for peace.[vii]

The accelerated globalization of the 20th century thus cultivated a new global consciousness at the city level,[viii] bringing such matters as human rights within the competence of subnational authorities.[ix] Thus, local officials justified intervention in foreign policy as a direct attempt to enforce the norms set forth in the UN Charter and Nuremberg principles, particularly when nations failed.[x] City diplomacy operated on this principle during the municipal foreign policy movement of the Cold War, when U.S. cities intervened in response to President Ronald Reagan’s arms race with the Soviet Union, inaction on apartheid, and funding of death squads in Central America.[xi] This “animus of the underling” principle continues to explain modern dynamics in city diplomacy, notably the response by U.S. local leaders to President Donald Trump’s announcement of his intent to withdraw from the Paris Agreement.

This response, involving direct subnational intervention to fill a federal governance gap in climate leadership, was facilitated by an important precedent and its associated bottom-up city diplomacy infrastructure. In 1974, University of California Irvine chemists Sherwood Rowland and Mario Molina discovered that chlorofluorocarbons (CFCs) were critically damaging Earth’s ozone layer. After tireless advocacy, this discovery led to the 1987 Montreal Protocol, whereby the nations of the world pledged to ban the then-common chemical.[xii] While this was the first UN treaty to be ratified by all UN member states, national government ratification did not necessarily translate to immediate action.

In 1989, the Irvine-based Center for Innovative Diplomacy, led by Irvine Mayor Larry Agran, policy entrepreneur Jeb Brugmann, and attorney Michael H. Shuman, responded to slow national implementation of the Montreal Protocol by implementing the first city-level CFC ban in the United States. They then partnered with Rowland himself to host the “North American Congress of Local Governments for a Stratospheric Protection Accord (SPA)” at UC Irvine. There, U.S. and Canadian local officials convened both to share knowledge on Irvine-style CFC bans and to pledge to create an international secretariat for similar local environmental initiatives. The UN Environmental Program (UNEP) took note of the SPA’s success, and in 1990, UNEP invited Irvine leaders to the UN headquarters to attend the “World Congress of Local Authorities for a Sustainable Future.” This congress convened over 200 local leaders globally to breathe life into the SPA’s envisioned international secretariat, thus establishing what was called the “International Council for Local Environmental Initiatives.”[xiii] Today, that organization is known as ICLEI – Local Governments for Sustainability (ICLEI), the world’s largest environmental transnational municipal network.

ICLEI paved the way for other environmental networks to grow, as other world cities increasingly responded to national failures by creating new city networks to share knowledge and resources about environmental policy best practices.[xiv] The advent of transnational municipal networks brought a structural evolution in city diplomacy which facilitated cities’ efforts to enforce norms violated or ignored by nations. This also paved the way for the later response to President Trump’s withdrawal from the Paris Agreement.  

Paris Pullout and Subnational Response

Following President Trump’s June 2017 announcement of his intention to withdraw the United States from the Paris Agreement, California Governor Jerry Brown and other U.S. subnational leaders forged the U.S. Climate Alliance. This coalition of U.S. states and cities promised to uphold the American commitment to the Paris Agreement from the bottom up. In furtherance of these commitments, they also established America’s Pledge, which aimed to track and quantify the impact of U.S. non-federal climate action, including local emissions reduction capacities, to fill the federal leadership gap. Given the absence of a U.S. federal government pavilion at the 23rd UN Framework Convention on Climate Change (UNFCCC) Conference of Parties (COP23), America’s Pledge opened an informal pavilion under the banner “America’s Pledge: We Are Still In.”[xv] Several states and cities from outside the United States also reaffirmed their commitment to the Paris Agreement by joining the U.S.-based Under2 Coalition of subnational governments for climate action, then under Governor Brown’s leadership. The 2017 North American Climate Summit in Chicago saw over 50 mayors from ten countries sign the “Chicago Climate Charter” pledging to achieve greater emissions reductions in order to fill the gap left by Trump’s withdrawal of U.S. federal support.[xvi] This bottom-up networked response by cities in the United States and beyond to act as global climate governance “norm sustainers”[xvii] was enabled in part by the environmental norm enforcement precedent of SPA and ICLEI surrounding the Montreal Protocol, as well as by the new global environmental governance structure for cities created in its stead.

Such conditions produce unique multilevel governance arrangements between nation-states and subnational authorities, where uncooperative national leaders are bypassed by counterpart nations that seek instead to make inroads with the norm-enforcing subnational leaders. [xviii] China’s President Xi Jinping met with California Governor Brown to address bilateral cooperation on climate change instead of President Trump.[xix] Likewise, Governor Brown met with Barbara Hendricks, the German Federal Minister for the Environment, Nature Conservation, Building and Nuclear Safety, regarding cooperation on sustainable economic growth and fighting unemployment.[xx]

City Diplomacy as Social Justice

The norm enforcement function of city diplomacy can serve to protect populations marginalized by or otherwise subjugated by unjust conditions at the hands of national-level forces. The traditional role of the nation-state as a guardian versus the role of cities as commercially concerned entities[xxi] blurs when considering the evolving role of cities in diplomacy. Might cities become guardians to an extent? The inclusive nature of city diplomacy brings about a democratization of foreign policy, one involving greater inclusion of traditionally less powerful voices long unheard. In this way, city diplomacy could advance social justice.

Local authorities, and especially indigenous communities, have been underrepresented in U.S. national policymaking on global climate change governance, a gap which President Obama attempted to fill by creating the State, Local, and Tribal Leaders Task Force on Climate Preparedness and Resilience.[xxii] In the absence of enduring national reform, such task forces tend to be temporary national attempts to improve representation of municipal locales in global processes. In the longer term, city diplomacy serves as one of the vital civic mechanisms to provide said representation.

City diplomacy as social justice underscores the guardian role for cities, particularly as U.S. federal statecraft increasingly operates on neoliberal principles that privilege commercial interests over national guardianship. A notable pattern in national behavior of this sort is the leveraging of fear, and racialized and xenophobic othering, to frame an anti-globalization message that is ultimately profit-oriented.[xxiii]

While not solely relevant to Presidents Reagan and Trump, their example is instructive. Reagan’s fearmongering on the spread of communism helped him to justify the lucrative arms race with the Soviet Union, anti-communist intervention in Central America, and ultimately tax cuts for the wealthy. Similarly, Trump’s racialized othering of Mexicans and Muslims, as well as fearmongering of financial exploitation by foreign countries, helped justify anti-immigration policy and withdrawal from the Paris Agreement, the latter of which profited oil industries. By privileging commercial profits over international responsibilities, neoliberal statecraft strips the state of its guardian and governance functions, and prompts a response through city diplomacy that seeks to advance social justice in the absence of national leadership. The test of city diplomacy as social justice is the extent to which it is used to induce national change and overturn nationally imposed systems of oppression: from authoritarian repression of dissent, to foreign defense policy that violates human rights, to the predatory capitalism that brings the slow death of poverty.

Autonomy, Regime Type and City Diplomacy

The political nature of a national regime can either enable or constrain city diplomacy. Less restrictive, more democratic national regimes tend to afford subnational authorities greater political autonomy, allowing locales to defy their national government in foreign policy and use local legislative power to codify universal norms. Conversely, non-democratic national regimes like China constrain such defiance but use city diplomacy as an extension of national diplomacy.[xxiv]

Even in longstanding democracies, city diplomacy can be attacked from the top, though the difference compared to autocracies and semi-democracies is that subnational autonomy tends to prevail. For instance, Australia’s Foreign Relations (State and Territory Arrangements) Bill 2020 sought to make foreign affairs the exclusive business of the national government, thus limiting city diplomacy.[xxv] Yet within Australia’s democratic national regime, this attempt at restricting subnational autonomy failed in much the same way as U.S. President Trump’s attacks on sanctuary cities for undocumented residents: not only did subnational autonomy prevail, the top-down attacks actually strengthened judicial protection for it.[xxvi]

While city diplomacy in democratic states is unique in its political autonomy from the national government, it is not innately resistant to cooperation with the national government. On the contrary, democratic states are formulating approaches to strengthen city diplomacy via national government assistance and coordination. In the United States, there are growing calls for the establishment of a “subnational diplomacy office” in the Department of State to serve such an assistance function, including bipartisan support from legislators in the form of the City and State Diplomacy Act (H.R. 3571) and various calls from scholars and practitioners.[xxvii] A functional pilot of such an office existed from 2010 to 2013, when Secretary of State Hillary Clinton appointed Reta Jo Lewis as Special Representative for Global Intergovernmental Affairs (SRGIA). Special Representative Lewis’s success in assisting U.S. mayors and governors to achieve international commercial, scientific, and political goals set a powerful example showing that national governments can effectively support infrastructure for city diplomacy.

The relationship between city diplomacy and national regime type is not a dichotomy between democratic versus autocratic systems, but rather a spectrum. The former Soviet bloc nation of Moldova is a fledgling democracy but is highly oligarchized, with corruption widespread throughout national and local officialdom. Moldovan mayors are observed to use international city branding and diaspora networks to build popularity and secure sufficient political power to avoid criminal punishment for corruption and build local fiefdoms.[xxviii] Cities in the young democracies of the Baltic nations, Estonia, Latvia, and Lithuania, engage in international networks and initiatives more with the aim of gaining new policy knowledge to solve self-governance problems than of engaging on larger diplomatic issues, which are left to national ministries. However, cities in the Baltic states nevertheless have and exercise the autonomy to express views contrary to that of their respective national governments.[xxix]

In nations with more restrictive, authoritarian national political regimes, subnational governments engaging internationally mostly do not express views contrary to that of their national governments. This is reflected in China’s authoritarian system, where city diplomacy is understood as an extension of national interests and power.[xxx] While many such regimes limit the international engagements of their cities, China is unique in that the government harnesses such engagement, institutionalizing city diplomacy through Foreign Affairs Offices (FAOs) at the municipal and provincial level, overseen by the central government. These offices enable Chinese cities to better engage in a range of sister city relationships, trade missions, and other international endeavors for local economic growth but also in furtherance of national foreign policy goals.[xxxi] Yet Chinese cities tend to participate less in transnational municipal networks and similar global governance initiatives than cities in other nations of commensurate economic size, due in part to the Chinese Communist Party strategically keeping international political power within the central government’s grasp. [xxxii] China’s institutionalization of city diplomacy through FAOs, however, is by no means exclusive to authoritarian regimes. It even offers a useful model that may be adapted for democratic or federal states to empower local governments with international competencies while also granting them full autonomy from national politics.

City diplomacy between cities of authoritarian and democratic countries can be instrumental in mending ties when national politics are engulfed in crisis. For instance, U.S.-China relations continued at the city level via sister city relationships after the 1989 Tiananmen Square massacre left nation-to-nation communication in virtual radio silence.[xxxiii] In 1990, the mayor of Shanghai made the first visit of any Chinese official to the United States following the massacre, traveling to Shanghai’s sister city of San Francisco in the first step toward rebuilding normal national diplomatic relations.[xxxiv]

The non-sovereign nature of city diplomacy also allows pursuit of diplomatic goals when matters concerning sovereignty are too politically tense. The island nation of Taiwan maintains its own democratic government and currency, yet lacks formal diplomatic recognition from other countries as a sovereign nation due to mainland China’s steadfast territorial claim. Taiwanese national and city governments bypass these problems through the use of city diplomacy. For instance, Taiwan’s New Southbound Policy is aimed at building economic and people-to-people ties with several South and Southeast Asian countries, which it navigates by using informal city-level international exchanges, often led by Taiwan’s capital city of Taipei.[xxxv]

Democracy Beyond the Sovereign Nation-State

The relationship between city diplomacy and democracy also reaches beyond the purview of nations and into new structures in global governance. Transnational municipal networks like ICLEI are governed democratically by member city governments,[xxxvi] a development the political scientist Chad Alger interpreted as democracy expanding beyond the sovereign nation-state.[xxxvii] These networks dot a new global landscape of polycentric systems of governance, where organized subnational authorities, nonprofits, and companies pursue global governance goals horizontally, largely independent from national governments.[xxxviii] The expansion of democracy beyond the nation-state is not only seen in the internal governance of polycentric systems, but also in the process by which they expand city representation in existing, formal global governance institutions. This can be illustrated through the example of the Local Governments and Municipal Authorities (LGMA) constituency within the UN Framework Convention on Climate Change (UNFCCC), the formal regime for climate governance among nations.

As nations gathered to negotiate climate change governance at the first Conference of Parties (COP) in 1995, the LGMA was also launched to represent local governments, albeit as mere observers, with ICLEI designated as the lead.[xxxix] After years of advocacy by ICLEI, local governments were first recognized as “governmental stakeholders” at COP16 in 2010.[xl] This was followed in 2014 by the establishment of the Non-State Actor Zone for Climate Action at COP20 to help increase national government climate mitigation commitments by integrating the commitments made by their respective subnational authorities.[xli] Efforts at subnational integration have continued through the 2015 Paris Agreement (COP21) and the meetings that followed, as it has become more evident that nations can better achieve climate action goals if they successfully integrate the efforts of subnational authorities as well as companies.[xlii]

Local Constituent-Official Alignment

Another principle of modern city diplomacy is the need for an alignment of foreign policy views between local constituents and the local officials implementing such policies. This condition enables city diplomacy activity and is most likely to occur within democracies, where strong civil society allows direct constituent interaction with officials.

As communities come to identify with the broader global community, they form global interests and initiate discourse between local officials and constituents on global issues, which may result in the passage of policy by city government that addresses their concerns.[xliii] The greater the perceived stakes on both sides of a given foreign policy issue, the more the implementation of a municipal foreign policy hinges on local official-constituent alignment.[xliv] Applicable policy agendas range from pursuing a local response to national transgressions in foreign policy to forging new international ties or taking new international-scale action independent of the national context.

This may be understood in terms of social movements literature, where the interpretive frames of a cause projected by social movement leaders become aligned with the interpretive frames of participants,[xlv] in this context occurring within the political process of constituents and government representatives.[xlvi] Whether municipal foreign policies are brought onto the municipal policy agenda first by city government officials themselves or by way of local constituent demand, local official-constituent alignment on foreign affairs issues is often a necessary condition for the implementation of a municipal foreign policy.

Former U.S. President Ronald Reagan’s funding of anti-communist death squads in Central America led to thousands of refugees fleeing to the United States and elsewhere. In American cities where local officials and constituencies aligned on the need to provide safe haven, officials responded by successfully implementing sanctuary city policies. Conversely, the Seattle City Council passed a sanctuary policy without consulting constituents, resulting in local constituent backlash that forced the council to rescind the sanctuary measure.[xlvii] This tradition continued into the 21st century, with U.S. cities establishing sanctuary jurisdictions for undocumented immigrants, in which local authorities were prohibited from inquiring into citizenship status.[xlviii] The Trump administration’s immigration policies, which included a travel ban from several majority-Muslim countries and the building of a Mexico border wall, added significant federal-level political pressure to sanctuary politics. In tune with these policies, Trump launched an attempted crackdown on sanctuary cities, threatening to stifle federal funding to them and even transport and deposit incarcerated undocumented immigrants into the sanctuary cities.[xlix]

American cities responded by establishing yet more sanctuary jurisdictions, while several states launched legal challenges to the Trump administration’s immigration policies. Cities where both local officials and constituents were politically aligned on sanctuary policies responded by establishing yet more sanctuary cities, and several state governments similarly launched legal challenges to Trump’s immigration policies.[l]

The state of California specifically responded by passing the California Values Act (SB54) in 2017, which made California a sanctuary state, and all cities within it sanctuary cities.[li] Don Wagner, then the mayor of Irvine, California, openly opposed SB54 and proposed a measure to revoke Irvine’s sanctuary city status under SB54. This led to local constituent backlash from individuals across civil society, education, industry and other sectors, resulting in the proposed measure quickly being removed from the municipal agenda.[lii] The lack of local constituent-official alignment on the sanctuary issue thus prevented implementation of the anti-sanctuary measure.

The Trump administration generated strong national-local policy tensions on existing and ongoing sanctuary policies, an ultimately counterproductive endeavor creating more sanctuary jurisdictions and actually strengthening judicial protection for undocumented residents.[liii] This outcome encouraged good governance, as sanctuary policy tends to provide for better local policing practices.[liv] As former Los Angeles Mayor Tom Bradley argued of sanctuary policy, the city has an obligation to provide all inhabitants with essential services regardless of citizenship status.[lv] American sanctuary politics of today still involve refugees from war-torn countries but also are defined significantly more by undocumented immigrants simply seeking a better life, and the obligation of which Mayor Bradley spoke has not changed.[lvi]

Economic Capacity, Competition and Risks

Urban economic growth interests permeate many city diplomacy endeavors, where opportunities to compete are delimited by a city’s economic capacity to engage internationally. This schema also brings the risk of power shifting to market actors, eroding the public good served by city diplomacy and bringing broader negative policy implications.[lvii]

In addition to normative factors, the pursuit of private capitalist interests also shape the diplomatic arena.[lviii] The international engagements of cities are normally aimed at improving the welfare of their local citizens, for instance, the export promotion used by Bavaria, Germany to promote growth in local industries.[lix] In the United States, foreign trade offices used for export promotion are set up most frequently at the state level but also at the city level, enabling direct foreign market entry opportunities for local exporting firms.[lx] International city-level trade missions are also conducted both as standalone efforts and are integrated into the annual exchanges of sister city relationships.[lxi]

China is particularly adept in this arena, as its city- and provincial-level Foreign Affairs Offices (FAOs) enable trade and investment promotion as well as technology exchanges between its cities and international counterparts.[lxii] This infrastructure, for instance, allows the Chinese city of Zhuhai to have representatives in the U.S. and other countries in order to create new market ties for the city. These and other intercity linkages generate bilateral job creation potential that might otherwise not occur, which serves as a key justification of their continuity.[lxiii] Beyond job creation, the international trade inroads established by cities can be instrumental in improving local crisis and emergency response. For instance, U.S. cities and states procured masks and ventilators for COVID-19 response from China, South Korea, and Canada, all via existing subnational linkages, in the absence of federal assistance.[lxiv] However, not all cities possess the budgetary wherewithal to engage in international exchanges in pursuit of market opportunities, leaving smaller cities with less opportunity to compete. China’s institutionalization of local FAOs in part reduces this problem, though in most other countries, international exchange, whether commercial, cultural, or diplomatic, remains a voluntary municipal effort rather than a nationally or externally funded endeavor.

These commercial activities require careful management to prevent excessive private sector influence on policymaking. In much the same way as expanded use of bonds and debt finance in municipal budgets has granted more power to financial market actors, commercial efforts in city diplomacy may risk transfer of agenda-setting power to corporate and other private actors if left unchecked.[lxv] The long-term risk is an urban policy-making setting that hinges less on government bureaucrats than it does on the decisions of investors.[lxvi]

Another risk is that of moral hazard. Cold War-era American cities divested from South Africa to pressure the end of apartheid via corporate withdrawal, forgoing the economic opportunity cost in favor of siding with human rights and antiracism.[lxvii]A modern conundrum in city diplomacy is that the same logic does not apply to U.S.-China relations, ostensibly because of the large size of the Chinese economy and interdependence of both economies. Bilateral commercial city diplomacy with China is informed both by the logic that trade with China does not directly perpetuate China’s human rights abuses and that in any case such matters are of a distinctly national-level political nature.[lxviii] However, American investments in South Africa also did not directly perpetuate apartheid policies, yet activist cities leveraged those relationships to implement anti-apartheid measures. This contradiction would suggest that the human rights ambitions of American city diplomacy is limited by the profit and economic growth opportunities present with a counterpart nation. If city diplomacy does not seek to induce change in undesirable national politics both domestically and abroad, it is relegated to either serving as a mere cog in the nation-state machine or simply serving the unambitious goal of economic growth.

Overlapping Global Urban Governance and Economic Systems

Economic logics in city diplomacy also extend to larger emergent systems, namely the polycentric governance systems of transnational municipal networks and the economic system formed by the world city hierarchy, both systems which are increasingly interlinked. Regarding the economic system, the world city hypothesis tradition of literature holds that intercity flows of capital formed by companies and other ties comprise a global network, forming a “world city hierarchy” where higher centrality equates to greater urban power in the world economy.[lxix] While previously studied as separate phenomena in global city studies, recent studies have shown that a higher position in the world city hierarchy is closely associated with more simultaneous city government memberships in transnational municipal networks.[lxx] Further, a higher position in the economic hierarchy affords cities the perception of being highly relevant in global policy discourses facilitated by transnational networks,[lxxi] and the networks themselves are increasingly establishing business partnerships beyond city governments.[lxxii]

The greater participation, presence, and representation in global urban governance thus afforded by centrality in the global urban economic system carries important implications for city diplomacy. The increased involvement of private sector actors in polycentric governance systems creates conditions conducive to the risks of neoliberal logic, where the interests of public sector actors are gradually overtaken by private interests.[lxxiii] If borne out, the risk to city diplomacy in the global governance sphere would involve sacrificing gains in transparency and representation in favor of more concentrated economic power among cities.[lxxiv] These broad risks may be managed by oversight from existing global urban governance systems, be they transnational municipal networks or larger institutions within the UN, which supervise emergent inequalities or monopolies created in these conditions and seek to define boundaries to limit them.

Another challenge in global urban governance involving private sector forces is corporate sustainability. The wealthiest private sector actors within cities, large corporations, are the most organized and expanding group of market actors undertaking climate action. Under the banner of corporate social responsibility, corporations are engaging in climate change mitigation, which includes policymaker engagement that can be impactful for environmental protection.[lxxv] However, the majority of companies still do not have climate action plans, and those that do are motivated in large part by market incentives, making accuracy in corporate sustainability performance reporting an ongoing concern.[lxxvi]

City diplomacy mechanisms offer potential solutions to these problems, beginning with the matter of co-location. A given city government carrying out a climate action plan is most often co-located with, or has within its jurisdiction, corporations both with and without their own climate action plans. Despite this proximity, city governments and corporations tend to be mutually ignorant of one another’s climate action efforts and in any case do not collaborate on these efforts. Traditionally, direct municipal government-corporate commiseration has involved city halls agreeing with local industry to deregulate environmental standards in order to maximize local economic growth, thereby increasing pollution.[lxxvii] That both city governments and the corporations within them are today undertaking similar climate governance efforts introduces a promising new context for direct local collaboration which may yield environmental benefits. Corporations govern their climate action efforts in a placeless manner, yet they are not placeless, and are well-placed to bridge their efforts in the urban governance sphere to which they are most proximate.

To that end, transnational municipal networks such as ICLEI and climate reporting repositories such as the Carbon Disclosure Project (CDP) should pilot municipal-corporate climate mitigation projects that facilitate direct collaboration between affiliated city governments and the climate-active corporations co-located with them. In addition to improving efficacy of the climate governance by the municipality and local corporations, this could chart pathways to developing accountability systems that allow accuracy concerns in corporate sustainability reporting to be more effectively addressed. Visibility and recognition gained by participating corporations in these local public-private endeavors could incentivize local non-climate active corporations to begin developing their own climate action plans, thus expanding corporate participation in climate mitigation from the bottom up.

Conclusion and Policy Implications

Given the above considerations, what might a healthy model of city diplomacy look like? Cities and nations alike would be wise to adopt a formula that includes the following elements.

Foremost is the need to expand data collection in a “smart city” fashion that can be scaled up to the national level. Enabling best practices and a better scientific understanding of city diplomacy requires that new data be collected on the international activities and relationships of cities, of subcity actors like companies and nonprofits, and on resources for cities to pursue international goals. These new data must be standardized and harmonized, including with existing data, to produce a full quantitative picture of international city-level connectivity.

A multilevel apparatus is necessary for data collection as well as for harnessing city diplomacy more broadly. This improved institutional infrastructure for city diplomacy should involve greater national government support for city diplomacy—without sacrificing local autonomy— as well as strong subnational institutions coordinating international affairs, linking both to national counterparts and to local public, private, and civic sector actors.

First, dedicated national government offices—at least one housed within the foreign affairs organ of the state—should be established to help subnational governments achieve international goals and afford them representation in global urban policy spaces. This includes coordinating subnational exchanges and partnerships with foreign counterparts, integrating local governments into multilateral processes and summits, and connecting locales to embassies and consulates abroad to maximize foreign market entry resources for internationalizing local firms. A national apparatus should also provide a space for managing inevitable and increasingly frequent central-local tensions, including negotiation of central-local disagreements on foreign policy and navigating judicial concerns surrounding autonomy and legal protections during disputes.

Second, local infrastructure in city halls and perhaps also at the state or provincial level should be put in place, allowing for a multilevel, whole-of-government approach to city diplomacy. Most effective would be a democratic repurposing of the Foreign Affairs Office model used in China, in which municipal and state or provincial offices are established with a corresponding national office, but the top-down national structure is replaced with a bottom-up orientation. This should involve defining the national role as one of support rather than command, maximizing local political autonomy as well as capacity to achieve international goals within the modern global system of cities.

National assistance in linking cities to global governance networks can expedite local achievement of desired goals and exhibit leadership in policy practice, as well as hasten collective progress made by global urban governance efforts. For example, by facilitating more city memberships in climate change networks like ICLEI, national institutions can accelerate municipal acquisition of climate policy knowledge needed to reduce urban greenhouse gas emissions. Multilevel coordination of this sort will help manage the growing complexity of global urban governance spaces, for example, as city governments and local corporations link together their own climate mitigation efforts, and existing international systems evolve to accommodate it.

This institutionalization of city diplomacy should also involve advancements in how local authorities engage constituents. City officials should establish consultative mechanisms with local constituents on global affairs issues to identify foreign policy areas of local importance and understand potential alignment or misalignment with officials. These mechanisms will enable city diplomacy to operate beyond a whole-of-government approach and reach a whole-of-society approach, drawing on civil society that strengthens city diplomacy. By these means the practice of city diplomacy can more fully integrate social justice and inclusion into its purview, integrating other underrepresented voices such as indigenous communities into international affairs. This can bring city diplomacy closer to grassroots social movements, closer to redressing grievances spurring these movements, and closer to dismantling systems of oppression upheld by national government or other actors, of domestic or foreign origin. In this way, the evolving agency of cities may develop a new system of checks and balances against abuses of power by the nation-state, and solutions to broader problems that transcend national borders.


[i] Benjamin Leffel, “Animus of the Underling: Theorizing City Diplomacy in a World Society,” Hague Journal of Diplomacy 13, no. 4 (November 2018): 502–22.

[ii] Leffel, “Animus of the Underling.”

[iii] Wesley Longhofer and Evan Schofer, “National and Global Origins of Environmental Association,” American Sociological Review 75, no. 4 (August 2010), 505–33; David John Frank, Ann Hironaka and Evan Schofer, “The Nation-State and the Natural Environment over the Twentieth Century,” American Sociological Review 65, no. 1 (February 2000): 96–116.

[iv] John W. Meyer, “World Society, Institutional Theories, and the Actor,” Annual Review of Sociology 36 no. 1 (2010): 1–20.

[v] Hedley Bull, “Does Order Exist in World Politics?” in International Relations Theory: Realism, Pluralism, Globalism and Beyond, ed. P.R. Viotti and M.V. Kauppi (Needham Heights, MA: Allyn & Bacon, 1999): 127–29.

[vi] James Fearon and Alexander Wendt, “Rationalism v. Constructivism: A Skeptical View,” in Handbook of International Relations, ed. Walter Carlsnaes, Thomas Risse, and Beth Simmons (London: SAGE Publications, 2002): 52-72; Martha Finnemore, National Interests in International Society (Ithaca: Cornell University Press, 1996).

[vii] Noé Cornago, Plural Diplomacies: Normative Predicaments and Functional Imperatives (Leiden: Martinus Nijhoff, 2013).

[viii] Richard V. Knight, “The Emergent Global Society.” in Cities in a Global Society, ed. Richard V. Knight and Gary Gappert (Newbury Park: SAGE Publications, 1989): 24–43.

[ix] Peter J. Spiro, “The States and International Human Rights,” Fordham Law Review 567, no. 66 (1997).

[x] A.F. Ginger, “From Morality to Law,” Bulletin of Municipal Foreign Policy 4, no. 1 (1989), 3.

[xi] Leffel, “Animus of the Underling.”

[xii] Thomas Hale, David Held, and Kevin Young, Gridlock: Why Global Cooperation Is Failing When We Need It Most (Cambridge: Polity Press, 2013).

[xiii] Nancy Skinner, “The Missing Link: City Leaders Unite to Save the Earth,” Bulletin of Municipal Foreign Policy 4, no. 4 (1990): 10–13; Jeff Sklansky, “CFCs’ Days Are Numbered: A New Greening of America Grips Local Officials,” Bulletin of Municipal Foreign Policy 3, no. 2 (1989): 8–12.

[xiv] Jale Tosun, “Diffusion: An Outcome of and an Opportunity for Polycentric Activity?” in Governing Climate Change: Polycentricity in Action?, ed. Andrew Jordan, Dave Huitema, Harro van Asselt, and Johanna Forster (Cambridge: Cambridge University Press, 2018): 152–68.

[xv] Mark Cooper, “Governing the Global Climate Commons: The Political Economy of State and Local Action, after the U.S. Flip-Flop on the Paris Agreement,” Energy Policy 118 (July 2018): 440–54.

[xvi] Tiffany Basciano, “Gotham Fights Back: The Role of U.S. Cities in Advancing Paris Agreement Goals Symposium: Transnational Perspectives on U.S. Withdrawal from the Paris Climate Agreement: Articles and Essays,” Maryland Journal of International Law 34, no. 1 (2019): 72–95.

[xvii] Sharmila L. Murthy, “States and Cities as ‘Norm Sustainers’: A Role for Subnational Actors in the Paris Agreement on Climate Change,” Virginia Environmental Law Journal 37, no. 1 (2019): 1–51.

[xviii] Liestbet Hooghe and Gary Marks, “Unraveling the Central State, but How? Types of Multi-Level Governance,” American Political Science Review 97, no. 2 (2003), 233–43; Taedong Lee, Global Cities and Climate Change: The Translocal Relations of Environmental Governance (New York: Routledge, 2015).

[xix] Jessica Meyers, “China Is Now Looking to California – Not Trump – to Help Lead the Fight against Climate Change,” Los Angeles Times, June 6, 2017,

[xx] Reta Jo Lewis, “Make America More Competitive: Engage Subnational Leaders and the Private Sector,” German Marshall Fund of the United States, July 13, 2017,

[xxi] Jane Jacobs, Cities and the Wealth of Nations (New York: Vintage, 1984); Jane Jacobs, Systems of Survival (New York: Vintage, 1992).

[xxii] The White House, “State, Local, and Tribal Leaders Task Force On Climate Preparedness and Resilience,” November 1, 2013,

[xxiii] Jagdish Bhagwati, “Anti-globalization: why?” Journal of Policy Modeling 26 (2004), 439-463.

[xxiv] Fritz Nganje, “The Developmental Paradiplomacy of South African Provinces: Context, Scope and the Challenge of Coordination,” Hague Journal of Diplomacy 9, no. 2 (2014), 119–49; Joana Setzer, “Testing the Boundaries of Subnational Diplomacy: The International Climate Action of Local and Regional Governments,” Transnational Environmental Law 4, no. 2 (2015), 319–37; Peter Bursens and Jana Deforche, “Going Beyond Paradiplomacy? Adding Historical Institutionalism To Account For Regional Foreign Policy Competences,” Hague Journal of Diplomacy 5 (2010): 151–71.

[xxv] Daniel Pejic, Anna Kosovac, and Michele Acuto, “New Foreign Relations Bill Puts ‘City Diplomacy’ at Risk,” Pursuit, The University of Melbourne, September 10, 2020,

[xxvi] Ilya Somin, “Making Federalism Great Again: How the Trump Administration’s Attack on Sanctuary Cities Unintentionally Strengthened Judicial Protection for State Autonomy Symposium: Reclaiming - and Restoring - Constitutional Norms,” Texas Law Review 97, no. 7 (2018), 1247–94.

[xxvii] Benjamin Leffel, Reta Jo Lewis, Corey Jacobson, Luis Renta, and Kevin Cottrell, “It Is Time for the United States to Institutionalize Subnational Diplomacy,” German Marshall Fund of the United States, 26 January 2021,; Anthony F. Pipa and Max Bouchet, “Partnership among cities, states, and the federal government: Creating an office of subnational diplomacy at the US Department of State,” The Brookings InstitutionFebruary 17, 2021,

[xxviii] Cristian Cantir, “Moldova’s Oligarch Mayors Go Global,” New Eastern Europe, no. 6 (November 16, 2020),

[xxix] Valentina Burksiene, Jaroslav Dvorak, and Gabrielė Burbulytė-Tsiskarishvili, “City Diplomacy in Young Democracies: The Case of the Baltics,” in City Diplomacy: Current Trends and Future Prospects, ed. Sohaela Amiri and Efe Sevin (Cham: Springer International Publishing, 2020): 305–30.

[xxx] W. Xiong and J. Wang, “City Diplomacy: A Theoretical Debate and the Features in Practice,” Public Diplomacy Quarterly (January 2013), 14–19; K. Zhao and W. Chen, “City Diplomacy: The Role of Global Cities in Diplomacy,” Foreign Affairs Review 6 (2013): 61–77.

[xxxi] Jian Junbo, Chen Zhimin, and Chen Diyu, “The Provinces and China’s Multi-Layered Diplomacy: The Cases of GMS and Africa,” Hague Journal of Diplomacy 5, no. 4 (2010): 331–56.

[xxxii] Hale, Thomas, and Charles Roger, “Domestic Politics and Chinese Participation in Transnational Climate Governance,” in Scott Kennedy, ed., China and Global Governance: The Dragon’s Learning Curve (London: Routledge, 2017): 250–71.

[xxxiii] Benjamin Leffel and Sohaela Amiri, “Sino-U.S. Sister City Relations: Subnational Networks and Paradiplomacy.” Rising Powers Quarterly 3, no. 3 (2018): 111–23.

[xxxiv] Mark Chandler, “Healing Sino-American Wounds,” Bulletin of Municipal Foreign Policy 4, no. 4 (1989), 36; Richard Trubo, “China: Back to the Future,” Bulletin of Municipal Foreign Policy 4, no. 3 (1989): 10–12.

[xxxv] Russell Hsiao, “Can City Diplomacy Promote the New Southbound Policy and Taiwan’s International Space?” Global Taiwan Brief 2, no. 29 (2017).

[xxxvi] Henner Busch, Lena Bendlin, and Paul Fenton, “Shaping Local Response – The Influence of Transnational Municipal Climate Networks on Urban Climate Governance,” Urban Climate 24 (June 2018): 221–30.

[xxxvii] Chadwick F. Alger, “The World Relations of Cities: Closing the Gap between Social Science Paradigms and Everyday Human Experience,” International Studies Quarterly 34, no. 4 (1990): 493–518; Chadwick F. Alger, “Searching for Democratic Potential in Emerging Global Governance: What Are the Implications of Regional and Global Involvements of Local Governments?” in The UN System and Cities in Global Governance, ed. Chadwick F. Alger (Cham: Springer International Publishing, 2014): 133–59.

[xxxviii] Elinor Ostrom, “Polycentric Systems for Coping with Collective Action and Global Environmental Change,” Global Environmental Change 20, no. 4 (2010): 550–57.

[xxxix] Jordi Borja and Manuel Castells, Local and Global: The Management of Cities in the Information Age (London: Earthscan, 1997).

[xl] UNFCCC, “Local Government Climate Roadmap: Cancun Outcomes for Local Governments,” 2011,

[xli] Thomas Hickmann, Oscar Widerberg, Markus Lederer, and Philipp Pattberg, “The United Nations Framework Convention on Climate Change Secretariat as an Orchestrator in Global Climate Policymaking,” International Review of Administrative Sciences 87, no. 1 (2019): 21–38.

[xlii] Angel Hsu, Niklas Höhne, Takeshi Kuramochi, Virginia Vilariño, and Benjamin K. Sovacool. “Beyond States: Harnessing Sub-National Actors for the Deep Decarbonisation of Cities, Regions, and Businesses,” Energy Research & Social Science 70 (December 2020).

[xliii] Kristin Ljungkvist, The Global City 2.0: From Strategic Site to Global Actor (New York: Routledge, 2015).

[xliv] Byron Miller, “Political Empowerment, Local-Central State Relations, and Geographically Shifting Political Opportunity Structures: Strategies of the Cambridge, Massachusetts, Peace Movement,” Special Issue: Empowering Political Struggle 13, no. 5 (1994): 393–406.

[xlv] David A. Snow, E. Burke Rochford, Steven K. Worden, and Robert D. Benford, “Frame Alignment Processes, Micromobilization, and Movement Participation,” American Sociological Review 51, no. 4 (1986): 464–81.

[xlvi] Doug McAdam, “Political Process Theory,” in The Wiley‐Blackwell Encyclopedia of Social and Political Movements, ed. David A. Snow, D. Della Porta, B. Klandermans, and Doug McAdam (Hoboken: Blackwell Publishing, Inc., 2013).

[xlvii] Leffel, “Animus of the underling.”

[xlviii] Bill Ong Hing, “Immigration Sanctuary Policies: Constitutional and Representative of Good Policing and Good Public Policy,” UC Irvine Law Review 2 (2012): 1–8.

[xlix] Rose Cuison Villazor and Pratheepan Gulasekaram, “The New Sanctuary and Anti-Sanctuary Movements Symposium: Immigration Law & Resistance: Ensuring a Nation of Immigrants,” U.C. Davis Law Review 52, no. 1 (2018): 549–70.

[l] Christopher N. Lasch, R. Linus Chan, Ingrid V. Eagly, Dina Francesca Haynes, Annie Lai, Elizabeth M. McCormick, and Juliet P. Stumpf, “Understanding Sanctuary Cities,” Boston College Law Review 59, no. 5 (2018), 1703–74.

[li] California State Senate, California Values Act, Senate Bill No. 54, Chapter 495, 5 October 2017,

[lii] Charis E. Kubrin and Bradley J. Bartos, “Sanctuary Status and Crime in California: What’s the Connection?” Justice Evaluation Journal 3, no. 2 (2020): 115–33.

[liii] Somin, “Making Federalism Great Again.”

[liv] Hing, “Immigration Sanctuary Policies.”

[lv] Michael H. Shuman, “A Message from the Editor,” Bulletin of Municipal Foreign Policy 1, no. 1 (1986), 6.

[lvi] Charis E. Kubrin and Benjamin Leffel, “California Sanctuary Cities Bill Is Humane and Effective,” The Hill, December 17, 2017,

[lvii] Jamie Peck and Heather Whiteside, “Financializing Detroit,” Economic Geography 92, no. 3 (2016): 235–68.

[lviii] Cornago, Plural Diplomacies.

[lix] Rodrigo Tavares, Paradiplomacy: Cities and States as Global Players (New York: Oxford University Press, 2016).

[lx] Samuel Lucas McMillan, The Involvement of State Governments in US Foreign Relations (New York: Palgrave Macmillan, 2012).

[lxi] Leffel and Amiri, “Sino-U.S. Sister City Relations.”

[lxii] Junbo et al., “The Provinces.”

[lxiii] Cheng Li and Xiuye Zhao, “America’s Governors and Mayors Have a Stake in US-China Relations,” The Brookings Institution, January 14, 2021,

[lxiv] Benjamin Leffel, Reta Jo Lewis, et al. “It Is Time for the United States to Institutionalize Subnational Diplomacy.”

[lxv] Peck and Whiteside, “Financializing Detroit.”

[lxvi] Margit Mayer, “Neoliberalism and the Urban,” in The SAGE Handbook of Neoliberalism, ed. Damien Cahill, Melinda Cooper, Martijn Konings, and David Primrose (London: SAGE Publications, 2018): 483–93.

[lxvii] Leffel, “Animus of the underling.”

[lxviii] Leffel and Amiri, “Sino-U.S. Sister City Relations.”

[lxix] Ben Derudder and Peter J. Taylor, “Central Flow Theory: Comparative Connectivities in the World-City Network,” Regional Studies 52, no. 8 (2018): 1029–40; John Friedmann, “The World City Hypothesis,” Development and Change 17, no. 1 (1986): 69–83; Saskia Sassen, Cities in a World Economy (Thousand Oaks: Pine Forge Press, 2006).

[lxx] Benjamin Leffel and Michele Acuto, “Economic Power Foundations of Cities in Global Governance,” Global Society 32, no. 1 (2018): 281–301.

[lxxi] David J. Gordon, Cities on the World Stage: The Politics of Global Urban Climate Governance (Cambridge: Cambridge University Press, 2020).

[lxxii] Michele Acuto and Benjamin Leffel, “Understanding the Global Ecosystem of City Networks,” Urban Studies, July 7, 2020,

[lxxiii] David Ciplet and J. Timmons Roberts, “Climate Change and the Transition to Neoliberal Environmental Governance,” Global Environmental Change 46 (September 2017): 148–56.

[lxxiv] Jeroen van der Heijden, “Studying Urban Climate Governance: Where to Begin, What to Look for, and How to Make a Meaningful Contribution to Scholarship and Practice,” Earth System Governance 1 (January 2019).

[lxxv] Thomas P Lyon, Magali A. Delmas, John W. Maxwell, Pratima (Tima) Bansal, Mireille Chiroleu-Assouline, Patricia Crifo, Rodolphe Durand, et al., “CSR Needs CPR: Corporate Sustainability and Politics,” California Management Review 60, no. 4 (2018): 5–24.

[lxxvi] Eun-Hee Kim and Thomas P. Lyon, “Greenwash vs. Brownwash: Exaggeration and Undue Modesty in Corporate Sustainability Disclosure,” Organization Science 26, no. 3 (2014): 705–23.

[lxxvii] Lazarus Adua and Linda Lobao, “The Growth Machine Across the United States: Business Actors’ Influence on Communities’ Economic Development and Limited-Government Austerity Policies,” City & Community 18, no. 2 (2019): 462–82; Allison Bridges, “The Role of Institutions in Sustainable Urban Governance,” Natural Resources Forum 40, no. 4 (2016): 169–79; Allan Schnaiberg, “Social Synthesis of the Societal-Environmental Dialectic: The Role of Distributional Impacts,” Social Science Quarterly 56, no. 5 (1975): 5–20