How Donald Trump could undo the Paris climate agreement

This segment originally aired Nov. 4, 2016, on VICE News Tonight on HBO.

“People signed up to ratify the Paris Agreement because of a force called ‘the Trump effect,'” 350.org founder Bill McKibben told VICE News. “He can still screw the whole thing up, but that’s what led people to move more quickly than they might otherwise.”

President-elect Donald Trump is vehemently opposed to the climate deal and has sworn that the U.S. will back out of it.

The Paris Agreement, by far the most meaningful and sweeping climate change deal ever signed, began to be enforced last week after the ratification by 55 countries. The ratification process was expected to take years. Instead, it took just 10 months.

“Prior to Paris, the principal approach was to get developed countries, countries like the United States and the European Union, to set very hard, strict targets, and then not ask anything of developing countries like China and India,” said Brian Deese, senior advisor to President Obama. “That didn’t work.”

The agreement reached a tipping point in September when the world’s two largest emitters, China and the U.S., ratified it. But its voluntary enforcement mechanisms have some observers questioning its effectiveness.

“The Paris Agreement is a beginning, but a very modest one,” McKibben said. “It’s important that it happened. But what’s going to be really important is to live up to those pledges.”

Read next: Trump’s rumored pick to lead the EPA wants everyone to “love global warming”

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