Editor's Note: This article is one of 50 in a series about Trump's first two years as president.

On the afternoon of June 1, 2017, a spectacular summer day with a wide-open sky and copious buttery sunlight, President Donald Trump stood squinting in the Rose Garden, and rewriting the future of the seasons.

“As of today, the United States will cease all implementation of the nonbinding Paris accord—and the draconian financial and economic burdens the agreement imposes on our country,” he said. Trump didn’t explain how the Paris Agreement on climate change—an international treaty meant to combat what scientists believe to be a catastrophic threat—could so “burden” the country if it was “nonbinding,” but not much about his speech that day made sense.

Two years on, there is little agreement about what Trump’s withdrawal from the Paris Agreement will mean. In the short term, the effects of his rollbacks of EPA regulations will overwhelm any environmental consequences of the pullout. But scholars fret that a long-term “Trump effect” —whereby Trump’s behavior and his policy choices could discourage investment in green technology, embolden polluting countries, and generally erode the trust necessary for international climate negotiations—could eventually discourage the rest of the world from cutting heat-trapping gas emissions. For instance, China may use Trump’s opening to pull back on its own environmental plans. And 2018 saw a right-wing backlash against climate-change policy seize the Anglosphere.

The Paris Agreement tried to encourage every nation to cut carbon pollution simultaneously—like a group of children who grab one another’s hands and jump into the pool together. By withdrawing from the agreement, Trump has significantly diminished the likelihood that this virtuous commitment to fighting climate change will continue to be mutually reinforced on a large scale.

Trump depicted his decision to withdraw as a heroic act intended to protect the American people. “As someone who cares deeply about the environment, which I do, I cannot in good conscience support a deal that punishes the United States—which is what it does,” he announced. The Paris Agreement doesn’t punish America, and Trump could have renegotiated the U.S. commitment under Paris at any time. In fact, he still can. But this was only one of many obvious untruths in his comments.

Of course, Trump’s decision to pull America out of an international climate treaty wasn’t unprecedented among recent Republican presidents: Almost exactly 16 years earlier, President George W. Bush confirmed that the United States would not honor the Kyoto Protocol, which would have been binding if the Senate had ratified it. Unlike Trump, however, Bush spoke eloquently of the problem that Kyoto sought to address. “The issue of climate change respects no border,” he said. “Its effects cannot be reined in by an army nor advanced by any ideology.” (Bush never matched those words with action, and he later questioned whether humans cause climate change. His administration never implemented a serious climate policy.)

Trump’s understanding of climate science is … less sophisticated than Bush’s. “We’ll be the cleanest,” he said during his comments about the Paris Agreement. “We’re gonna have the cleanest air. We’re gonna have the cleanest water,” he continued, without explaining how this was going to be achieved absent a climate policy. And he gleefully rejects the very idea of scientific expertise, insisting that he understands the climate better than the scientists in his own government. “One of the problems that a lot of people like myself—we have very high levels of intelligence, but we’re not necessarily such believers,” he said recently. “You look at our air and our water, and it’s right now at a record clean.” He did not specify how an atmosphere choked with greenhouse gas could be “record clean.”

Perhaps the president’s apparent indifference to climate change should not be surprising—because, after all, he seems indifferent to climate.  Whereas his predecessors liked to stretch their legs in the great outdoors—Bill Clinton jogged around the National Mall; George W. Bush rode a bike around his ranch—Trump’s exposure to nature tends to be limited to steering a golf cart around his resorts. He is fed on McDonald’s and fanned by HVAC. Ours is a vast and beautiful country. Our president is an indoor man.

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