U.S. President Barack Obama delivers remarks during the COP21, United Nations Climate Change Conference, in Le Bourget, outside Paris, on Monday, Nov. 30, 2015.AP Photo/Evan Vucci

This article is from the archive of our partner National Journal

Not long ago, the prospects for serious international cooperation against climate change appeared as bleak as the chances do today for meaningful international military action against ISIS.

Yet an international conference now meeting in Paris is moving toward an historic global agreement to curb the carbon emissions linked to destabilizing changes in the climate. Obstacles remain, and any agreement won’t completely resolve the problem. But the accord likely to emerge from Paris will commit the world to significant steps against a complex and multigenerational challenge that no nation can solve alone. 

In that way, the climate breakthrough offers important insights for forging more concerted action against ISIS, another ominous challenge that demands global cooperation. The most important lesson may be that, while the United States cannot solve global problems alone, the world is unlikely to move seriously against the toughest challenges without American leadership demonstrated by the willingness to accept political risks at home. President Obama has shown such a commitment on climate, but not on ISIS—which helps explain why he can celebrate so much more momentum on the former.

It’s worth remembering how meager the prospects for international progress appeared after the last global climate conference fizzled in Copenhagen in 2009. That gathering nearly capsized amid disagreements between industrialized and developing nations—particularly the United States and China—over how to allocate responsibility for reducing emissions. Optimism about international action ebbed further after the Senate in 2010 shelved Obama’s “cap and trade” plan to limit U.S. carbon emissions.

This downward trajectory was reversed in June 2014, when Obama announced Environmental Protection Agency regulations to reduce carbon emissions from existing U.S. power plants. His administration’s move ignited intense Republican opposition that continues unabated in Congress, the courts, and conservative states. In a national poll released this week by the Chicago Council on Global Affairs, less than one-third as many Republicans as Democrats called climate change a critical problem.

But Obama’s willingness to take on such politically contested action demonstrated a commitment that increased pressure on China, which had supplanted the United States as the world’s largest carbon emitter, to act as well. When Obama and Chinese President Xi Jinping agreed in November 2014 to a joint program to reduce the use of carbon, the accord precipitated a cascade of commitments from other nations—183, in all, had pledged cutbacks before the Paris conference convened this week. 

“In order to get China, you had to demonstrate that you were willing to do something serious at home,” says Ivo Daalder, the Chicago Council’s president and formerly Obama’s ambassador to NATO. “The EPA regulations on coal emissions [from power plants] showed we were willing to take the pain. And once the United States convinced China that they, too, bear responsibility for dealing with this challenge, others had to fall in line.”

In several respects, it’s tougher to mobilize international action to fight ISIS than the changes in climate. China agreed to constrain carbon emissions partly because of international pressure but also because its stygian pollution problems are generating growing unrest at home. By contrast, while ISIS is a critical cause for the United States and Western Europe, the countries closest to the front have higher priorities. Turkey worries most about combating the Kurds; Saudi Arabia, about containing Iran; Iran and Russia, about sustaining bloodstained Syrian President Bashar al-Assad. 

And while experts agree on how to combat climate change—by replacing fossil fuels like coal with more energy efficiency and renewable power—there’s no such agreement about how to defang the Islamic State. “On climate change, the science is clearer about what you need to do to get a real impact than … on counterterrorism,” Daalder notes. Moreover, the biggest political danger in confronting climate change is raising energy prices and antagonizing powerful fossil-fuel industries. That’s not easy anywhere. But risking casualties in a full-scale military campaign against ISIS is far more explosive politically.

Yet all this only underscores that other nations are unlikely to commit more in the fight against ISIS than America does. If the United States won’t pursue a serious military effort to dislodge ISIS from its strongholds in Iraq and Syria—an effort that includes a meaningful, if not massive, number of American ground forces—others likely won’t either. As on climate, Obama may only persuade others to take political risks to confront ISIS if he accepts them himself.

Obama is right that attacking ISIS won’t solve the generational problem of Islamic radicalism. But after the attacks in Paris, the menace of allowing ISIS safe havens where it can plan further terrorist strikes suggests the need to separate that long-term challenge from the immediate imperative to disrupt the organization. 

Again, the Paris climate conference offers a useful precedent. No one pretends it will secure emission reductions sufficient to stabilize the global climate; eventually, all nations will need to do more. But it isn’t usually possible to save the world in a single bound. Progress more often comes by taking a first step that enables another. Obama has recognized this on climate change. He needs to see it as clearly on the Islamic State. 

This article is from the archive of our partner National Journal.

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