President Donald Trump delivers a statement on the Iran nuclear deal from the Diplomatic Reception Room of the White House in Washington, May 8, 2018. Credit: Evan Vucci | AP

President Donald Trump believes in the art of disruption, of deliberately creating crises to get his way. That’s how he operated in business; it’s how he ran his presidential campaign. Now he’s applying the principle to American diplomacy.

When Trump announced last week that he was withdrawing the U.S. from its 2015 nuclear deal with Iran, he described it as an easy decision: “When I make promises, I keep them.”

The president predicted with breezy optimism that breaking the deal would lead to a better agreement in the future, one that would not only impose tougher limits on Iran’s nuclear research but force Tehran to change its entire foreign policy as well.

But he never explained exactly how he’d pull that off. And that’s the central flaw of Trump’s move. It’s long on self-confidence but weak on strategy. It scraps an agreement that stopped Iran from building nuclear weapons and replaces it with, well, it’s not clear. Which makes it, in the end, a gamble.

What is the president’s plan, as far as we can tell? Beyond reinstating U.S. economic sanctions on Tehran and hoping reluctant allies will play along, there isn’t one.

That’s not just my diagnosis; it’s the conclusion of the reluctant allies the president is counting on for help after he spurned their pleas to stay inside the multinational deal.

“What is the plan B?” French President Emmanuel Macron asked after meeting with Trump last month.

“His experience with North Korea is that when you are very tough, you make the other side move, and you can try to go to a good deal,” Macron told reporters. That “can work in the short term, but it’s very insane in the medium to long term.”

In the case of North Korea, the U.S. has significant leverage: international economic sanctions backed by a commitment to eliminate Kim Jong Un’s nuclear threat by U.S. force. In Iran, the international sanctions were dismantled as a result of the agreement, and no other country has offered to join the U.S. in re-imposing them. Instead, Britain, France, Germany, Russia and China have all expressed their intention to keep the nuclear deal in force.

If, once U.S. sanctions are back in place, the Trump administration tries to punish European banks or oil companies for doing business with Iran (as U.S. law requires), that will create a crisis pitting the U.S. against its own allies.

And that would suit Iran fine. Iranian President Hassan Rouhani says he’ll stay in the agreement as long as other countries continue to buy his oil. Some experts believe that China may even increase its oil purchases from Iran, especially if it gets a distress-sale discount.

The history of economic sanctions has yielded one clear rule: Unilateral sanctions, even from a country as powerful as the U.S., never work. (See Cuba, where a tyrannical regime has withstood a U.S. trade embargo for more than half a century.)

But let’s imagine that the Treasury Department gets tough on Europe, makes sanctions effective and does damage to Iran’s already sputtering economy. Does it seem likely that Tehran will meekly sign a new agreement with the president who walked away from the previous accord?

That’s a hope, not a strategy. But that’s what the president says will happen.

“Iran’s leaders will naturally say that they refuse to negotiate a new deal … and that’s fine,” Trump said. “I’d probably say the same thing if I was in their position. But the fact is they are going to want to make a new and lasting deal.”

Maybe. Or the regime might collapse, an outcome Trump didn’t call for explicitly but seemed to hint at. Or Iran’s hardliners, with their backs against the wall, could revive their nuclear-weapons program and confront the West with the choice of going to war or accepting a nuclear Iran. That’s the eventuality the deal was designed to avoid.

As Macron told Germany’s Der Spiegel when asked about the most likely consequence of U.S. withdrawal: “That would mean opening Pandora’s box. It could mean war.”

And that’s the gamble. Trump’s decision is likely to be remembered as a blunder unless it turns out to be a catastrophe.

Along the way, though, the president will have accomplished at least one historic feat. For decades, other countries have looked to the U.S. for leadership to avert global crises. But under Trump, the U.S. is creating crises and relying on others to solve them.

Memo to the president: They don’t give Nobel prizes for that.

Doyle McManus is a Los Angeles Times columnist.

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