U.S. President Donald Trump said Monday that he will announce his policy on the nuclear agreement with Iran on Tuesday. Trump has until May 12 to decide whether to sign the 120-day waiver on U.S. sanctions against Iran. On his own, he cannot determine the fate of the Joint Comprehensive Plan of Action (JCPOA): Officially, the United States is just one of its signatories, alongside Russia, China, Great Britain, Germany and France – and, of course, Iran. The remaining governments, which all continue to support the Iran deal, could theoretically keep it alive. However, not only did the United States play the key role in achieving the deal under then-President Barack Obama, but its economic and military clout make any American move potentially disastrous for the JCPOA’s chances of survival.

Trump could take one of a number of courses of action and, depending on how the other signatories act, it could lead to different results. One scenario that is implausible is that after spending the last two years – both on the campaign trail and then as president – lambasting the JCPOA as the “worst deal ever,” Trump will suddenly back down and endorse his predecessor’s foreign policy legacy.

Whether he decides to “fix or nix it,” Trump plans to either radically change the Iran deal or do away with it altogether.

Iran nuclear deal: Anshel Pfeffer interviews former Israeli General Amos Yadlin

Here are the five likeliest scenarios:

1. Waiver signed with caveats – Death by a thousand cuts

After all the hue and cry of the last few weeks, Trump signs the waiver again (as he has done every four months since taking office). But he will do so with a host of caveats. Adding to the pressure, this time the waiver may be for a shorter period than 120 days. Trump will say he is still against the JCPOA, but is giving the European leaders who have beseeched him to stick with the deal one last chance to come up with improvements that are not just “cosmetic.”

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This will serve Trump, as it will shift the pressure away from Washington and allow the administration to focus on preparing for the upcoming summit with North Korea’s leader, Kim Jong Un.

This is unlikely to save the Iran deal, though – just prolong its demise. The proposals that have so far come from Germany and France have included new sanctions on Iran’s long-range missile plan and proposals for new ways to counter Iran’s machinations in the region, but have failed to satisfy the U.S. administration – particularly because the other signatories refuse to change the JCPOA in order to address the “sunset” time-limit issue.

Iran nuclear deal: Anshel Pfeffer interviews former Israeli General Amos Yadlin Credit: Haaretz

Another waiver, another delay will not save the deal if Trump and his newly appointed Secretary of State Mike Pompeo and National Security Adviser John Bolton are determined to ultimately kill it by a thousand cuts.

The lingering uncertainty over the deal’s future is almost as damaging to the faltering Iranian economy as a resumption of sanctions. But if the painful death can be drawn out for even longer, why not?

2. No waiver, no action, more delay

Another way for Trump to increase pressure while shifting the blame elsewhere is to not sign the waiver, but not rush to re-impose sanctions either. The sanctions that target Iran’s central bank, and are mainly aimed at hampering its international oil deals, do not come into effect for another 180 days – effectively giving the administration and the other signatories five more months to search for a compromise. The clock would be ticking and there would be two new deadlines: In another 180 days, but also over a second, wider batch of sanctions that must be decided upon on July 11.

At this point, the Europeans will be scrambling in both directions: To try to find a solution that could still make Trump backtrack and sign the waivers, better late than never; and, at the same time, prevent the Iranians from pulling out of the JCPOA. Not that it would be in Iran’s interest to do so, since that would automatically trigger sanctions, but they have repeatedly issued statements that they will not agree to any prevarication from the other signatories. As Foreign Minister Mohammad Javad Zarif tweeted two weeks ago, it’s “all or nothing.” Except it never really is all or nothing, and playing for time would probably serve the Iranians just as it serves Trump.

3. No waiver, new sanctions, a split between the U.S. and Europe

The die is cast. Trump not only refuses to sign the waiver, but his administration acts to reimpose sanctions with an accelerated timetable. Whatever these sanctions target – nuclear-related sectors or other Iranian activities – Tehran will cry foul and pronounce the JCPOA dead. But it could still leave the door open to a compensation deal from the other signatories. Russia and China will play along, but they were trading with Iran before the JCPOA as well.

This scenario could well be the biggest diplomatic dilemma in the European Union’s history. The EU is also a signatory, but EU foreign policy chief Federica Mogherini – a valiant cheerleader for the Iran deal – will be powerless if the leaders of Britain, France and Germany won’t agree on a joint policy. Theresa May, Emmanuel Macron and Angela Merkel will each have to make independent decisions on whether to defy the United States and join a new Iran deal without the Americans, or fall in line with the Trump administration.

This is a momentous decision for the main Western European nations. Do they act against their own stated policies, or open up an unprecedented rift between Europe and the United States? The stakes are particularly high for “Brexit Britain,” which is on course to leave the EU next year. If France and Germany stick with the JCPOA, despite Trump, Prime Minister May’s government will have to decide which relationship they are more loath to jeopardize.

The stakes are particularly high for Britain, as London is still a major global financial hub both for banks and insurance companies. The City of London played a central role in imposing the sanctions on Iran at the start of the decade – and will be crucial in either renewing the sanctions or trying to counteract them, should Britain join the international coalition trying to save the Iran deal.

For Iran, and for Russia and China as well, a major crisis in the U.S.-European relationship, potentially endangering NATO’s cohesion, would be a huge achievement. On its own, it could be a worthwhile incentive for Iran to remain within the JCPOA framework, despite the United States pulling out.

4. Iran symbolically resumes its uranium enrichment

Depending on the severity of the new sanctions and the European response, Iran will have to decide whether to make do with threats to pull out of the JCPOA – but remain with it so as not to lose billions of dollars-worth of sanctions relief – or to pull out for real. Of course, it could first try a middle way. The main component of the deal from the Iranian side is self-imposed limitations on uranium enrichment. With nearly a third of its total of 19,000 centrifuges still operational but currently either not enriching uranium or enriching it only to the relatively low level of 3.67 percent, resuming pre-JCPOA levels to up to 20 percent, or reactivating the centrifuges that the deal still allows to have at the Fordow facility (for research purposes only), would not take long. Recent satellite footage of increased activity around Fordow could point to contingency plans to do just this.

Open gallery view Map locating Iran's Nuclear facilities Credit: Reuters

Increasing enrichment to pre-JCPOA levels would be in contravention of the deal, but Iran could claim it was the United States that broke the agreement first. And it would not yet be enriching uranium at weapons-grade levels, so it could claim to still be acting within the parameters of the non-proliferation treaty (NPT). Iran would claim it was only asserting its rights for peaceful nuclear research, not working on a weapons program. But it would once again be on the threshold of the “breakout” to a bomb.

While such a move would precipitate a crisis, it could still be reversible – a bargaining position. It may serve to make all the sides stop and think. But that’s assuming either the Trump administration or the hard-line faction in Tehran, which has already proven stronger in recent months than the “moderate” faction led by President Hassan Rohani, want to step back from the brink.

Another element that could come into play at this stage is Iran’s Revolutionary Guards’ Quds force operating in Syria or Lebanon. According to Israeli intelligence, Iran has for weeks been planning a revenge attack on Israeli targets, following the airstrikes against Iranian bases in Syria attributed to Israel.

While the shadow war between Israel and Iran on Syrian soil is seemingly a separate conflict, any escalation on that front will feed directly into the decision-making of all sides on the nuclear issue as well. If a revenge attack is launched, it’s impossible to see how the Trump administration could scale back sanctions or the Europeans make a convincing argument for doing so.

5. Both sides on the brink

The Iran deal was the result of both the United States and Iran reaching the tacit understanding that a diplomatic compromise in the form of an arms-control deal, however unsatisfactory, was preferable to the prospect of war. Obama may have repeatedly said “all options are on the table,” but few in the region were ever convinced he was willing to contemplate the military option against Iran – while Iran trumpeted its rights to nuclear development, but was ultimately prepared to limit those rights in return for the removal of sanctions.

Both sides of that equation have fundamentally changed with the election of Trump and the ascendancy of the hard-liner faction in Tehran, which was never in favor of the JCPOA to begin with.

How far either side is willing to go now has yet to be seen. The closest thing to a doomsday scenario would see the United States preparing for war in the wake of sanctions, with the biggest military buildup in the Middle East since the eve of the Iraq War in early 2003. That is what it would take if the Iranian response is not just a symbolic ratcheting up of uranium enrichment, but “breakout” – an all-out dash across the nuclear threshold.

In such a case, it will be a no-holds-barred race to prevent Iran from reaching the finishing line that North Korea recently succeeded in crossing. That means war – in Iran, and quite likely in other countries that will be sucked in, including Saudi Arabia, Syria, Lebanon and Israel.

Such a scenario still seems far-fetched, but all it would take is a decision in Tehran to change strategy and try to use the period of uncertainty over the JCPOA to win nuclear immunity. Out of the question? Just ask Kim Jong Un how it works.