This is less so when it comes to the other six global threats. For example, war and weapons are controlled by the nation’s government, not by the governments of cities or states. Thus, when California voted to support the U.N.’s 2017 Treaty on the Prohibition of Nuclear Weapons(1), the state’s decision had no effect on the US government’s decision to keep (and even modernize) its nuclear arsenal. On the other hand, the local or regional influence over the environment is greater. When California enacted stricter tailpipe emission standards on all new vehicles than those prescribed by the U.S. Environmental Protection Agency, American car manufacturers followed California’s rules, not the EPA’s. Californians buy so many cars that the industry could not afford to lose their business.(2) Such subnational power is has come to be called “the California effect,” and presumably other states can wield it too–at least if they set standards in a collective way.

That is why individual states or cities sometimes join forces when demanding a particular environmental policy. Examples include the C40 cities, the ICLEI, and the Global Compact Cities Programme (organized by the UN but with 127 member cities worldwide). Such associations resemble voluntary “clubs” more than governments, for the organization generally has no real jurisdiction over decision-making. Nevertheless, they can share information and resources, and also set high standards for themselves. These standards help them negotiate with their national governments or such multilateral institutions as the World Bank or the International Monetary Fund, which do wield real power. And cities are increasingly adopting new and higher standards, as for example in August 2018, when 19 cities, including Paris and Tokyo, pledged to make all of their new buildings carbon neutral by the year 2030, and to impose the same strict standards on the old buildings by retrofitting them by 2050. London’s mayor has also promised that his city will emit zero carbon by 2050.(3)

Alliances or coalitions of cities have existed for many centuries, especially in Europe, where municipalities have traditionally enjoyed considerable political autonomy, even when the region was governed by a monarch or feudal lord. For example, during the Middle Ages a number of Germanic cities formed the Hanseatic League, which was quite effective in managing trade relations, though it was not in any sense a state. Today’s “movements of cities” are not merchants managing their trade relationships, but rather mayors seeking to manage the environment and especially limit global warming. That should surprise no one. About half of the world’s population live in cities— and by 2050 that figure may be 70 percent.(4) Cities must expect increasing disasters, such as floods, especially when the sea level rises.

C 40 Cities Climate Leadership Group is a network of 94 megacities around the world that facilitates dialogue among city officials. Today one in twelve persons on the planet is represented in the organization by a mayor.

The network was formed in 2005 when Ken Livingstone, the mayor of London, convened representatives from 18 megacities. The following year, he invited Bill Clinton’s organization, the Clinton Climate Initiative, to become a partner. By then, the network had grown to 40 major cities—hence the name C40 was chosen. They established a secretariat in London and formed a steering committee which began holding workshops to exchange best practices.(5)

In 2008 Toronto’s mayor, David Miller, took over and in 2009 organized the Copenhagen Climate Summit for Mayors and another summit in Seoul. He was succeeded in 2010 by Mayor Michael Bloomberg of New York City, who has continued active engagement in the organization and who provides substantial funds; even in 2019 he is the chairman of the board. He chaired the C40 for three years and organized summits of mayors in São Paulo and Johannesburg, while the membership of the organization grew to 63 cities.

At the São Paulo meeting the C40 announced new partnerships with the World Bank and ICLEI (Local Governments for Sustainability) to accelerate climate action in cities through better greenhouse gas accounting and uniform reporting.(6)

Mayor Bloomberg was succeeded by Mayor Eduardo Paes of Rio de Janeiro, who helped launch the Global Covenant of Mayors for Climate and Energy. Today the organization is chaired by Mayor Anne Hidalgo of Paris. In 2016 the C40’s sixth summit was held in Mexico City and attended by 1,400 people

C-40’s chair is the elected leader of the organization, which is managed by the C40 Board of Directors. The steering committee consists of various mayors who serve in rotation and provide strategic policies. Each member city acts independently, according to its unique situation, but they band together when their collective power can be used to obtain resources, such as technical and financial support. They maintain that they can take bolder risks and can act at lower costs through working together than would be possible if each city acted alone. Today cities that are not large enough to qualify as “megacities” can be admitted to the organization if they have shown leadership and innovation in environmental and climate change work.

ICLEI (pronounced ICK-LY but whose real name is “Local Governments for Sustainability”) is another worldwide organization of sub-national governments. It was founded in 1990 as a worldwide network of cities, towns, and regions working toward a sustainable future.(7) By 2019 it consists of more than 1,750 local and regional government in over 124 countries, where it maintains 22 offices. Over 37 percent of the global urban population is represented in the network, as indeed also is more than 20 percent of the whole global population.(8) In 2019 its president is Ashok Sridharan, Mayor of Bonn, Germany.

At its 2018 World Congress in Montréal, ICLEI adopted a plan of action up to 2024.(9) Much of their work is devoted to making cities resilient–prepared for various disasters that must be expected with the advance of climate change. For example, ICLEI held a conference in China that picked 28 cities in that country as pilot cities for planning for climate adaptation.

Occasionally organizations such as ICLEI and C-40 are opposed by right-wing nationalists, who argue that these networks, like all others connected to the United Nations, somehow undermine private property and the sovereignty of the nation states where they are located.(10)

The United Nations Global Compact is a much wider organization than the mayors’ organizations mentioned above. Its member organizations are not only cities but also corporations. Indeed, it was originally created by U. N. Secretary General Kofi Annan in 1999 entirely to promote corporate social responsibility among business firms. The General Assembly promptly mandated it as an initiative for furthering responsible business practices and UN values.

However, in 2001, it was decided that cities as well as corporations should be allowed to join the UN Global Compact. As a result, the UN Global Compact – Cities Programme was launched the following year, with its International Secretariat initially located in Melbourne, Australia.

Melbourne became the first city to engage the Global Compact in June 2001. There are, as of 2016, over 130 member cities in the programme. There are also 85 Local Networks are independent, self-governed groups that help companies and non-profit organizations promote responsible business practices. For example, a Local Network in Bulgaria consists of 20 leading companies and organizations in partnership with the government, local authorities, labour organisations and civil society organizations. (11)

The compact’s 13,000 corporate participants and other stakeholders in over 170 countries support such initiatives as “Principles for Responsible Investment” and the United Nations Conference on Trade and Development (UNCTAD). On the other hand, the compact is not a legally binding document, and it has sometimes been criticized for being endorsed by businesses simply for the sake of “greenwashing” themselves; their pledges do not carry over into their real practices. (To “Greenwash” is to pretend to be responsible mainly for the sake of the firm’s public reputation.) Where legally binding obligations are absent, greenwashing exists as a potential option.

Mayors for Peace. Although most of the sub-national governments and non-state networks are concerned with environmental and climate issues, a few such organizations focus on other topics, including human rights and military policy. One important organization of that sort, Mayors for Peace, originated in 1982 at the 2nd UN Special Session on Disarmament held at the UN Headquarters in New York. Hiroshima’s Mayor Takeshi Araki urged cities to jointly demand the elimination of all nuclear weapons.

Accordingly, the mayors of Hiroshima and Nagasaki formed an organization that they named “The World Conference of Mayors for Peace through Inter-city Solidarity” and invited every mayor in the world to join. In 2001, the organization changed its name to “Mayors for Peace.” It is based in Hiroshima, whose mayor always serves as its president. As of April 2019, the organization has 7,745 member cities in 163 countries and regions. Cities that endorse its core document, (12) are called “solidarity cities.” They sponsor workshops or meetings on peace, disarmament, and security issues. They also address other broader problems, such as famine, refugees, human rights abuses, and environmental degradation. In 2003 they established their “2020 Vision” campaign, the main vehicle for advancing their goal: a nuclear-weapon-free world by the year 2020. Now of course they are promoting the “Treaty on the Prohibition of Nuclear Weapons,” which was adopted at the United Nation in 2017 and will come into force after 50 states have ratified it. Mayors for Peace will then be devoted to the next challenge: inducing the nuclear weapons states to comply with the treaty, which unfortunately is not likely to occur by the year 2020.

Provinces and States. Environmental impacts are sometimes determined as much by provincial policies as by national governments, and often change is also easier to implement at those sub-national governments. In the United States, at least, most of the mitigation innovations are being introduced by states–and, as previously noted, especially by California.

In September 2018 that state hosted a three-day summit in San Francisco for representatives of cities and regions everywhere who mean to reduce their carbon emissions. Jerry Brown, then serving his final months as governor of the state, had “non-state actors” everywhere to join this gathering, where the best methods of monitoring progress would be showcased. Research was unveiled there showing that such innovations as improving the efficiency of generating electricity and public transportation could create 14 million new jobs and prevent 1.3 deaths from pollution each year by 2030.(13) Just before hosting the event, Governor Brown signed legislation to shift California to 100 percent carbon-free electricity by 2045.(14) At that time, almost everything will be powered by electricity instead of fossil fuels.

Such innovations are catching on elsewhere. According to Non-State Actor Zone for Climate Action (NAZCA), a record-keeping service maintained by the United Nations, about 2,500 cities, 209 regions, over 2,100 firms, and nearly 500 investors pledged during 2018 to reduce their carbon footprint.(15)

This sounds impressive, but is it enough? Philip Drost, a researcher at the UN Environment Programme, thinks not. The problem is that most pledges are not spelled out as specific, quantifiable goals and there are often no mechanisms defined for measuring progress. Moreover, those goals that are made specific often are targets that would have been reached anyway. The real achievements fall short of what is going to be required.

Nevertheless, subnational actors may eventually be the main forces that press national governments–and even other localities–to move faster. One new organization was founded at Jerry Brown’s conference: the Under2 Coalition, which expects to recruit 250 subnational governments, which collectively can cut between 15 and 21 billion tonnes of CO₂ by 2030.(16)

The real question is whether local action can adequately make up for inaction on a national or international scale. The answer is not clear yet. Let’s hope that we never have to find out.

Endnotes for this article can be seen at the Footnotes 4 page on this website (link will open in a new page).