The Realist Case for Climate Change Cooperation

World leaders should use the Paris climate talks this week to form an alliance against the threat of climate change.

A Yemeni shepherd walks a herd of goats through a drought-affected dam on the outskirts of Sanaa, Yemen, on June 17, 2014. (AP/Hani Mohammed)
A Yemeni shepherd walks a herd of goats through a drought-affected dam on the outskirts of Sanaa, Yemen, on June 17, 2014. (AP/Hani Mohammed)

The most important international security conference of the year begins today in Paris. More than NATO or the U.N. Security Council, the 2015 U.N. Climate Change Conference is grappling with the most serious long-term risk to international security: climate change. The decisions made at the conference—often referred to as the 21st Conference of the Parties, or COP 21—will shape the next phase of a generational fight against the destabilizing effects of climate change.

Fighting climate change is often considered a valuable but secondary goal for many security-minded politicians who see it as a distraction from the real threats posed by terrorism in Syria, Russian aggression in Europe, and the potential of a nuclear Iran. But even a hard-nosed realist should support international cooperation on climate change. Due to climate change’s impact as a “threat multiplier,” the benefits of cooperation now outweigh the potential gap in relative gains between cooperating countries. When climate change is viewed as an external threat similar to a hostile state, realist theory concludes that the United States should ally with other threatened countries against it until the threat subsides.

Realism and the relative gains problem

Realism, one of the grand theories of international relations, is a worldview and set of assumptions about the way the world works that dates back to Thucydides of ancient Greece. Realism has long been the dominant strand of thinking in U.S. national security circles and undergirds much of U.S. foreign policy. Realist scholars, such as Kenneth Waltz, focus on the state as the primary actor in international politics; assume anarchy in the international system is the principal force shaping state action; and believe states are primarily concerned with their own power and security—often at the expense of mutually beneficial cooperation.

Realist scholars and practitioners have traditionally spent little time devoted to climate change compared with adherents of liberalism—the other grand theory of international relations. For realist theorists focused on hard power and interstate warfare, debates about peak carbon dioxide emissions and global temperature goals are ancillary at best to the primary challenges facing states. Furthermore, realists such as Joseph Grieco are skeptical of the potential for international cooperation on most issues, arguing that even when cooperation would be mutually beneficial to both parties, states often fail to cooperate because one state would gain more than the other.

This is known as the relative gains problem. Realists argue that states are not only concerned with maximizing their own absolute gains but they are also concerned with their gains relative to the gains of other states out of concern that they may end up relatively weaker even if they are stronger in absolute terms.

But the relative gains problem does not prevent all forms of cooperation, even when one state gains disproportionately. For realists, the main reason that a state would cooperate is if the gains of cooperation are so large that they overcome the relative gains problem—a threshold that is usually only met when states face an external security threat.

Climate change as an external security threat

For years, scientists have warned of the potential implications of the current wave of changes to the Earth’s climate. 2014 was the hottest year ever recorded and continued a trend of rising sea levels that threaten major coastal cities and even some island nations, as well as more intense and frequent severe weather events, increased desertification of vital arable land, and climate-driven migration, which has contributed to the European refugee crisis.

If the most pessimistic projections are realized without international action, the planet could warm by as much as 5 degrees Celsius by the end of this century. To put it another way, that is the same as the global temperature change that occurred during the last ice age but at 10 times the speed. Failure to limit climate change and better manage global resources will soon disrupt the physical and economic security of citizens across the planet.

Climate change does not fit the traditional realist image of a security threat, but as climate change intensifies existing conflicts and exacerbates instability, states are increasingly being forced to grapple with and defend against it, just as they would a hostile adversary. Whether through the extreme weather events that have killed 2.5 million people since 1980, the rising sea levels that threaten to swallow island nations such as the Maldives, or the droughts that doubled the price of wheat in the lead up to the 2011 Arab uprisings, climate change is threatening lives, destabilizing states, and disrupting economies in ways an adversarial state might using different means.

U.S. intelligence, military, and diplomatic agencies are already thinking through the security implications of a warming planet, an acidifying ocean, and an increase in extreme weather events. In 2008, the National Intelligence Council began a multiyear project analyzing the implications of climate change for U.S. national security interests between 2008 and 2030 and concluded that climate change would likely exacerbate political instability, migration crises, and intrastate warfare. The U.S. Department of Defense’s “2010 Quadrennial Defense Review Report” identified climate change as one of the key issues that will shape the future security environment, affecting the U.S. military’s capabilities, missions, and operations. The U.S. Department of State’s 2015 “Quadrennial Diplomacy and Development Review” highlighted climate change as a “national and global security threat,” as well as one of the department’s four strategic priorities.

For U.S. security officials, climate change now meets the high threshold used by realists for international cooperation, regardless of a potential relative gains gap.

An alliance against climate change

Realists such as Stephen Walt argue that when faced with a hostile external threat, threatened states will band together, creating an alliance to counter the threat and to restore a balance of power in which no one actor can overpower the others. These alliances are usually narrow and short-lived, lasting until the threat—whether it be Napoleonic France or the Islamic State of Iraq and al-Sham—recedes. If the threat of climate change is now comparable to the threat of a hostile state, then the realist response would be to develop an international alliance against climate change.

President Barack Obama’s administration has largely adopted this approach, enlisting not only traditional European and Japanese allies in the effort but also nontraditional partners such as China, India, Brazil, and Indonesia. The direct and indirect threat posed by climate change has altered the calculus of countries such as China and India, which previously cited the principle of common but differentiated responsibilities as a reason for not fully contributing to a global effort to fight climate change. This is in part a relative gains argument that says unified action to combat climate change would disproportionately hurt economically developing and newly industrialized states in light of differing national circumstances. The diverse range of countries participating in the alliance against climate change reflects the new geopolitics of the issue, in which both developing and developed countries are affected by, contribute to, and thus are responsible for fighting the problem.

As with alliances against hostile states, the alliance against climate change should not be expected to remake the global order or resolve disagreements with partner countries on other issues. As history has shown, however, the United States can successfully work with nontraditional partners or even competitor states to combat a common threat, whether improving relations with China to counter the Soviet Union in the 1970s or leading a diverse coalition of nations to fight piracy off the Horn of Africa more recently.

The Paris climate conference this week is in many ways a capstone to the Obama administration’s multiyear efforts in bilateral, minilateral, and multilateral forums to build an international consensus in the fight against climate change. Codifying the expectation that even developing countries such as China and India must meaningfully contribute to the fight—and continue to contribute to the fight in the lasting climate regime the Paris agreement is set to establish—is a crucial step to ensuring a sustainable, effective alliance against climate change.

As President Obama said in a speech to the U.S. Coast Guard earlier this year, denying the threat posed by climate change and failing to use all of the resources at the nation’s disposal to defend the country against it would be a “dereliction of duty.” The president’s comments may sound hyperbolic, but that is simply the realist in him speaking. Climate change is the greatest long-term risk to global security. A realist analysis of the issue says it is time world leaders start acting like it.

Ken Sofer is a Senior Policy Advisor with the National Security and International Policy team at the Center for American Progress.

The positions of American Progress, and our policy experts, are independent, and the findings and conclusions presented are those of American Progress alone. A full list of supporters is available here. American Progress would like to acknowledge the many generous supporters who make our work possible.


Ken Sofer

Senior Policy Adviser