Can the World Address Climate Change Without the US?

For many environmental advocates, the COP30 climate negotiations ended this weekend in disappointment. The annual United Nations conference, which brought together more than 190 countriesin Belém, Brazil, concluded without any firm plans to phase out fossil fuels—a key step scientists say is urgentlynecessary to address the climate crisis.

In part, experts say, that’s because of the United States, which had been noticeably absent from the summit. While more than 100 local US leaders reportedly attended, including California Gov. Gavin Newsom, the Trump administration sent zero delegates—marking the first time in the talks’ 30-year history that leadership from the world’s largest economy (and largest historical emitter of CO2) had no official presence.

At the beginning, says Matt McDonald, a professor of international relations at the University of Queensland in Australia, the lack of an American delegation may have offered a sense of “relief” to some countries hoping to negotiate bold climate action. Donald Trump, after all, might be something of a wet blanket at a climate conference; he has repeatedly referred to climate change as a “hoax,” and withdrew from the Paris climate agreement twice.

But as the talks continued, McDonald says, the vacuum left behind by the US may have also “emboldened” petrostates like Russia and Saudi Arabia to resist plans to move away from oil, coal, and gas.

Indeed, much like the Paris agreement 10 years ago, the lukewarm agreement officials ultimately settled on at COP30 doesn’t include the term “fossil fuels.”

“A climate deal without explicit language calling for a fossil fuel phaseout is like a ceasefire without explicit language calling for a suspension of hostilities,” climate scientist Michael E. Mann posted on Bluesky.

That’s despite the fact that, at this year’s conference, the first draft of an agreement proposed several suggestions on ending the international fossil fuel habit. More than 80 countries rallied behind the idea. “This is an issue that must not be ignored, cannot be ignored, and we are saying very, very clearly must be at the heart of COP,” said UK energy secretary Ed Miliband.

“The intensity and the clarity of this call was new and unprecedented in the history of COPs,” said Genevieve Guenther, a founding director of End Climate Silence.

“There’s certainly been a break from some of the same ways of talking about thinking about discussing pathways forward,” said Max Boykoff, a University of Colorado Boulder climate communications researcher at who attended the conference.

That was perhaps facilitated by the US’ absence, which Boykoff said “provided a motivating push for the rest of the world to say, ‘This is time for us to be stepping forward.'”

How exactly the coalition of nations backing a fossil fuel phaseout crumbled is a mystery; the press is not allowed to observe negotiations, but global oil powers reportedly lobbied hard for its exclusion. By the end of the weekend, the goal set out under the 2015 Paris agreement—to limit warming to below 2 degrees Celsius—seemed further away than ever.

But as McDonald sees it, while the overall climate outlook isn’t great, there are reasons not to abandon all hope for climate action.

As he noted in a piece for The Conversation in October, the world is making modest progress on CO2 emissions, with or without the US. Some scientists believe emissions are close to peaking, he writes, driven in part by “unprecedented global investment in renewable energy.” China, currently the largest emitter of carbon emissions, although still very much invested in fossil fuels, has also invested record-breaking amounts in renewable energy, particularly wind and solar, and has committed to reducing carbon emissions by at least 7 percent by 2035.

“China is an economic realist,” McDonald says, operating with the long-term understanding that “renewables are going to be where it’s at, rather than fossil fuels.” Still, he notes, China did little to advocate for a fossil-free agreement at COP30, largely avoiding the debate.

Individual US states can make a dent in global emissions, too. “California is the really obvious example,” McDonald says, “because it is incredibly consequential for global emissions. It’s a massive economy”—the fourth in the world, to be exact, and home to one of the largest carbon-trading markets.

In Belém, Newsom was among the most vocal US leaders to attend, reportedly saying that Donald Trump’s absence was an “opportunity” for local leaders to step up. “He pulled away,” Newsom told reporters, according to the Guardian. “That’s why I pulled up.”

Even without all countries on board, a significant subset of climate-minded nations could have real impact. In response to the lack of global consensus on dropping fossil fuels, a group of at least 24 countries, led by Colombia and the Netherlands, has announced that it will hold a counter-conference in April to establish a plan to do just that.

“There is a world in which these nations band together and create a global trading bloc that could essentially force the petrostates to start decarbonizing,” says Guenther. “I’m not claiming this would be easy,” she says, “but I’m saying it could be a way forward.”