Just two countries refused to partake in the Paris Agreement, the historic climate deal to cut greenhouse gas emissions that was signed by nearly every nation. One of them, Syria, is in ruins after six years of ongoing civil war. The other, Nicaragua, boycotted the accord to protest its unambitious initial goals and its failure to legally bind countries to their emissions targets.

The one other holdout, Uzbekistan, finally signed onto the agreement last month.

But now President Donald Trump is poised to withdraw the United States ― which was largely responsible, under the Obama administration, for orchestrating the deal ― from the Paris Agreement.

In 2016, Trump campaigned on a promise to “cancel” the deal, which he said put an unfair burden on the U.S. and gave poorer countries a pass. The U.S., second only to China in its amount of carbon pollution, committed to slashing emissions by 26 to 28 percent below 2005 levels by 2025.

Former President Barack Obama planned to meet that goal largely by reducing pollution from the utility sector, by far the country’s biggest emitter. To do so, he passed a sweeping regulation called the Clean Power Plan, which put limits on emissions from power stations and encouraged the proliferation of zero-emissions energy sources such as solar and wind. Trump has already moved to dismantle that policy.

Khalil Ashawi/Reuters Syria, in fairness, has some other things to deal with beyond cutting its greenhouse gas emissions.

Despite Trump’s campaign pledge, the White House has been under intense pressure to stay in the Paris Agreement. Secretary of State Rex Tillerson, Energy Secretary Rick Perry, adviser and first daughter Ivanka Trump and her husband, adviser Jared Kushner, support remaining in the deal, albeit with some tweaks to the emissions target. Big corporations, including oil giant Exxon Mobil Corp., also warned Trump against quitting the agreement.

On the other side of the debate are Environmental Protection Agency chief Scott Pruitt, a virulent anti-climate hard-liner, and chief strategist Steve Bannon, who is widely credited with shaping the president’s nationalist views and nurturing his suspicion of international agreements.

As of now, the latter camp appears to be winning. Trump is leaning toward deciding to exit from the Paris Agreement as early as next week, multiple sources with knowledge of the plans told HuffPost on Tuesday. The agreement allows for countries to pull out three years after the accord takes effect, meaning the administration could officially withdraw on Nov. 9, 2019, according to a State Department legal memo obtained by HuffPost. The withdrawal would be complete one year later.

The memo notes that the U.S. “could announce a plan to withdraw and reduce or cease participation in Paris Agreement activity earlier.”

Doing so would likely isolate the U.S. diplomatically, make rival superpower China the moral leader on climate change and crush any hope of strengthening targets under the Paris Agreement when they come up for renegotiation a decade from now.

It would also put the U.S. in a club that includes a war-torn, terrorist hotbed dictatorship and a country with a gross domestic product lower than the valuation of the struggling social network Twitter. American exceptionalism, indeed.