“As I have said many times the Iran deal was one of the worst and most one-sided deals the United States has ever entered into,” said Donald Trump in his speech on Friday announcing that he did not intend to re-certify the Iran nuclear deal. Trump is not always a paragon of consistency, but in this case, he tells no lie. He has consistently railed against the Iran deal since the beginning of his presidential campaign, vowing to “renegotiate” it when in office. So how did we get here?

What does the deal contain?

After years of false starts, failed negotiations and accusations that Iran was violating the non-proliferation treaty they had ratified in 1970, the agreement, known as the Joint Comprehensive Plan of Action was struck in 2015, bringing together the United States, Iran, France, Germany, the United Kingdom as well as the previously recalcitrant China and Russia. 

The United States and other countries agreed to lift nuclear sanctions on the condition that Iran agreed not to pursue nuclear weapons, and to allow continuous monitoring of its compliance (another ongoing point of contention pre-JCPOA era). 

What constitutes ‘not pursuing nuclear weapons’? 

The deal places limits on centrifuges and uranium enrichment for 15 years after the agreement. Iran must reduce its uranium stockpile by 98%, from 10,000 kilograms to 300. And at the time of signing the deal, Iran had 20,000 centrifuges. Under the agreement, it must phase out the majority of these, and is limited to no more than 5060. The levels are such that Iran can continue to use nuclear power for energy needs. If Iran is found to be breaching its end of the the deal, sanctions are to be re-imposed.

The major concerns centered on whether Iran, given its history of duplicity on nuclear weapons may simply continue with a covert nuclear program that inspectors are unable to detect. However, the broad consensus among experts was close to a “best case scenario”.

As James Acton, co-director of the Nuclear Policy Program and senior associate at the Carnegie Endowment, told Defense News: “You can’t compare this to a perfect deal, which was never attainable.”

However, many raised objections, particularly around the 15-year time limit, after which Iran can produce as much nuclear fuel as it wishes. While most countries (including Australia) applauded the deal, Israeli Prime Minister Benjamin Netanyahu called it a “historic mistake”, which would bring about a “terrorist nuclear superpower”.

Mark Dubowitz, chief executive of the Foundation for Defense of Democracies, argues that the deal has “fatally flawed architecture”:

“It gives Tehran patient pathways to nuclear weapons and intercontinental weapons simply by waiting for key restrictions on its nuclear and missile programs to expire or sunset … As the deal currently stands, Iran gets all of this simply by complying. That is why the deal, as currently constructed, is detrimental to the vital national security interests of the US.”

What’s Trump’s problem?

During the campaign, Trump said — in vague, non-committal terms — the deal was so bad it was “suspicious”, telling a rally in Missouri, “It’s almost like there has to be something else going on … I don’t think there is, I just don’t think they’re competent.”

His criticisms have been broad; that the deal included no provisions for the return of American prisoners, and that Iran hasn’t lived up to “the spirit of the deal“.

Has Iran kept to its side of the deal?

According to Politifact, when Iran has breached its obligations under the deal, those breaches have been small, technical and quickly rectified.

Twice Iran has crept above the limit the agreements imposed on “heavy water” — a modified liquid used in some nuclear reactors. However, Iran does not currently have a functioning heavy-water reactor, so this did not bring the Islamic republic any closer to a nuclear weapon.

“A complex, technical process like this one is inevitably going to face small hiccups,” Ariane M. Tabatabai, visiting assistant professor at Georgetown University’s School of Foreign Service, told Politifact. 

Even critics of the deal, such as Dubowitz, aren’t alleging any specific non-compliance. By the same token, even supporters of the deal concede that while it has been effective in limiting Iran’s ability to develop nuclear weapons, it has barely improved Iran’s behaviour in other areas — its role as a destablising factor in regional conflicts (in Yemen, Syria and Iraq in particular), and continuing to test conventional ballistic missiles and, as Trump says, detaining US citizens.

Does ‘de-certify’ mean Trump is tearing the deal up?

No, at least not yet. The agreement require that the US President certify every 90 days that Iran is holding up its end of the bargain. He’s done this twice since taking office, but is now refusing. This basically kicks the decision to Congress, who can either rewrite the deal according to Trump’s wishes, or if they don’t, face the likely response that Trump will cancel the deal outright. They also will have 60 days to decide whether to re-impose sanctions on Iran.

So what does Trump want changed?

He wants to get rid of the sunset clauses that will allow the lifting of restrictions on Iran’s uranium enrichment post-2025, curbing of the ballistic missile testing Iran says it has been doing, and sanctions on Iran’s revolutionary guard, which he calls the “Iranian Supreme Leader’s corrupt personal terror force and militia.” 

What does Iran say about all this?

Iranian President Hassan Rouhani has been relatively unconcerned in his public statements so far, telling reporters outside the UN general assembly: “We don’t think Trump will walk out of the deal despite (his) rhetoric and propaganda.”

What might happen now?

As long as Trump has been threatening to dismantle the deal, people in his administration have been urging him not to. Just after Trump’s election victory, then CIA director John Brennan said to do so would be “the height of folly” — empowering hardliners in Tehran, and potentially sparking a nuclear arms race in the Middle East. Our very own Nobel Peace Prize winners — the International Campaign to Abolish Nuclear Weapons — have expressed similar concerns, with executive director Beatrice Fihn saying Trump is “igniting new conflict rather than reducing the risk of nuclear war”.