States are uniquely well-positioned for climate leadership internationally.

The traditionally nation-state-dominated arena of global climate change governance has become increasingly populated by subnational governments and the coalitions and networks they form. Contra the existing unitary, state-centric and top-down structures of the United Nations (UN), this has produced a new international plane of climate mitigation activities where multiple centers of bottom-up power and influence exist, a growing landscape of “polycentric climate governance.”[1]

While this new plane operates independently from and parallel to traditional global climate governance structures, the two are also increasingly collaborating with one another, a trend being called “hybrid multilateralism.”[2] In both cases, subnational actors are demonstrating their crucial potential to reduce greenhouse gas (GHG) emissions and thus directly contribute to climate governance goals pursued by the nations of the world. Illustrative of this potential is the case of the State of California, its subnational coalition building both globally and vis-à-vis the U.S. and China, and the resultant direct support for Paris Agreement goals in the absence of U.S. federal leadership.

As the structures of global climate governance evolve, so too does the conduct of international communication. Whereas the role of local governments in traditional public diplomacy was to communicate the will of national governments abroad,[3] the new public diplomacy involves subnational authorities pursuing their own international policy communication goals.[4] A live example is the ongoing response by local authorities to U.S. President Trump’s mid-2017 announcement of intent to withdraw the U.S. from the Paris Agreement, as leading subnational authorities in California and elsewhere are using public diplomacy channels to communicate, inspire and recruit more participants to fill this federal leadership gap. These dynamics are embedded in larger, broader contexts beyond just the issue environmental protection and the current era. Subnational diplomacy involves state/provincial and/or local leaders claiming political authority in foreign affairs,[5] which may be in opposition to national policies, may fill the void of policy leadership left by ineffectual national governments, or may assist national governments by adding capacity from below.

The late Cold War saw many examples of subnational diplomacy in opposition to national policies.[6] Throughout the 1980s —fearing nuclear annihilation via the U.S.-Soviet arms races —nearly 4,000 locales in 17 countries, including hundreds in the U.S., declared themselves nuclear-free zones, prohibiting nuclear weapons production-related activities to take place within their jurisdictions.[7] City governments organized into broader efforts to advocate for nuclear abolition, through creating organizations such as Mayors for Peace and convening meetings such as the World Conference of Mayors for Peace Through Inter-city Solidarity in Hiroshima.[8] After the Reagan administration and Congress failed to place hard corporate sanctions on Apartheid South Africa, U.S. cities divested $450 billion worth of stock in companies that did business in South Africa,[9] and by 1990, 59 cities, 25 states and 13 counties had enacted some type of legislation banning investments in South Africa.[10] Civil war in Central America induced by the Reagan administration’s funding of anti-communist forces resulted in several U.S. cities establishing sister city relationships with Central American cities to send aid, as well as declaring themselves sanctuary cities and states for refugees fleeing from the region.[11] Even the State of Wisconsin became a sanctuary state,[12] reflective of California’s recent decision to do the same.[13]

Subnational diplomacy used for supplementing national efforts from below has been seen in its application for peacebuilding. For example, after the war between Serbia and Croatia ended in 1995, a range of Croatian municipalities via UN intervention cooperated to restore ethnically fair distribution of public services, facilitated inter-ethnic trust building, and ultimately helped prevent ethnic violence in the post-conflict period. The Municipal Alliance for Peace in the Middle East was created via The Hague in 2005, which used joint initiatives with the Association of Palestinian Local Authorities and the Union of Local Authorities of Israel to facilitate municipal cooperation between Palestinian and Israeli local authorities, and contribute to much-needed trust building.[14]

The varied applications of subnational diplomacy have also found local actors assuming new roles as sponsors, facilitators and communicators of public diplomacy, where “enhancing communication between localities may result in better perception and understanding of the countries involved and represented.”[15] For instance, Taiwan faces difficulties in achieving economic and public diplomacy goals due to lack of formal diplomatic recognition; however it bypasses these difficulties by using sister city relationships and other city government international networking mechanisms to create new trade, investment and branding opportunities.[16]