Donald Trump decertifies Iran nuclear deal

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It was the deal almost nobody wanted. Now it is under threat again. US President Donald Trump has told Congress that a nuclear agreement with Iran is no longer vital to America's national security. The deal was meant to limit Iran's nuclear programme, in exchange for limited sanctions relief. In 2015, the most extraordinary global action saw seven countries and the UN Security Council endorse the plan.

It was the crowning achievement of Barack Obama's foreign policy, but Donald Trump calls it the worst deal ever. For both, however, Congress was a thorn in their side. For Obama, because Congress wanted nothing to do with the deal. For Donald Trump, because the risk in kicking it to Congress is that they blow it apart entirely. That means that all of Trump's touted skills, the art of the deal, are about to be put to the test.

One can almost set the countdown clock to when Iran can resume its nuclear weapons programmes it's nuclear--

The Trump administration says it wants to fix the deal and take a harsher overall strategy towards Iran, something that will tackle its ballistic missile programme, and what the US says is its malign influence across the region. But getting the deal in the first place was a hard-won effort. Almost uniformly opposed by Congress across the bipartisan divide, and it started in utmost secrecy.

Jake Sullivan, one of the initial negotiators, remembers the first time he was dispatched to try to open up a back channel with the Iranians.

So I dropped off the trip in Paris, without really explaining to anybody else on the trip why, and got on a flight to Muscat, to Oman, where I was met at the terminal by representatives of the Omani government, and whisked off in a car. And that is how the secret negotiations with Iran for the nuclear deal began. I had to constantly second guess whether it was the right thing to do or not. That was only responsible. In any diplomatic negotiation, you're never going to get everything you want, and you're always going to have to give up things you don't want to have to give up.

Mark Dubowitz, an Iran hawk who advised the Obama administration on a sanctions regime, dismisses worries that the deal signatories including Europeans and Iran, will not renegotiate.

I think the Iranian threat to walk away from the deal is overstated. The threat of the walk-away paralysed US-Iran policy under President Obama, and it's led the Europeans to be really terrified of any kind of coercive enforcement posture.

Iran's detractors have resorted to extreme coercive measures to prevent it gaining a military-grade nuclear programme in the past. Its nuclear scientists have been assassinated. Unprecedented cyber attacks burrowed into its uranium-enrichment facilities. But Trita Parsi, who argues for greater engagement with Iran says the deal is the only thing that has ever worked.

There's never been any example of the United States managing to change a core policy of the Iranians in any significant way in the last 37 years, with the exception of this nuclear deal. If you have found a path that works, and you are reneging on it to go down a path that you know hasn't worked, perhaps you're not looking for success. You're looking for failure, because this is a path that will lead to war.

The stakes are extremely high. Some in America allege Europe is more interested in saving its business prospects in Iran than pursuing lasting peace-- an accusation that could put the transatlantic alliance under the strain. European allies have been throwing themselves into the fight to save this deal.

And they've been making some headway suggesting ideas in which implementation could be, in theory, tightened without actually abrogating the deal itself. But it's not clear if they or Congress will get anywhere close to the fix Mr Trump wants, or how Iran and others will react. The future for now looks very messy. For the Financial Times, this is Katrina Manson in Washington, DC.