If there is anything coherent about Donald Trump’s presidency, it’s the consistency with which he’s tried to undo his predecessor’s policies, both foreign and domestic. He has scrapped the Trans-Pacific Partnership, the Paris Climate Accord, and scores of Obama-era executive orders. He cheered the repeal of the Affordable Care Act’s individual mandate. Now, with the appointment of bellicose former UN ambassador John Bolton to be his next national security adviser, the president seems more likely than ever to shred what he calls “the worst deal ever”—the Iran nuclear agreement.

The Joint Comprehensive Plan of Action (JCPOA), adopted in October 2015, removed sanctions against Tehran in exchange for placing strict limits on its nuclear program. To Trump, it was a “one-sided transaction” whose billions of dollars in lifted sanctions and direct payments enables a dictatorship to better fund its regional adventurism and terrorist proxies. Then there are the deal’s sunset provisions, which remove certain restrictions after 10-15 years. “What is the purpose of a deal that, at best, only delays Iran’s nuclear capability for a short period of time?” he asked in October.

But the terrifying paradox, to some observers, is that in his eagerness to avoid a nuclear-armed Iran, President Trump may not only involve the U.S. in a military conflict, but produce a bomb-ready adversary far earlier than he feared under the deal Obama struck.

In January, Trump announced that if the deal’s eight signatories couldn’t amend it to his liking by an arbitrary deadline of May 12, the United States would walk away. The intent, no doubt, was to confront the terror-supporting autocrats with alacrity, rather than with what he saw as his predecessor’s reticence. But changing a multi-lateral international agreement takes time, and this ultimatum leaves U.S., European, Russian, and Chinese diplomats little of that. In all likelihood, as Trump surrounds himself with hawkish voices like Mike Pompeo for secretary of state and Bolton, who has called for pre-emptively attacking Iran and engineering a regime change there, the president is preparing not for a signing ceremony, but for a walkout.

That could instigate a crisis, veteran Iran watchers worry. “There’s a probability of things getting out of control that could lead to higher friction and a military confrontation with Iran,” said Uzi Arad, a former national security adviser to Israeli Prime Minister Benjamin Netanyahu.