The Iran nuclear deal – formally, the Joint Comprehensive Plan of Action or JCPOA – is under pressure. In his speech to the UN General Assembly today, 19 September, President Trump called it “one of the worst and most one-sided deals” and said it is “an embarrassment to the United States.” Some commentators already see this as advance notice that the US will pull out of the agreement. But it was a good deal when it was made in 2015, it is being properly implemented, and it should be upheld.

The deal traded off confidence that Iran’s nuclear programme would offer no threat to any other state, with lifting economic sanctions, allowing Iran back into the international trading fold.

President Trump has the task of certifying to US Congress every three months that Iran is complying with the deal and that the agreement is in the US national security interest. This is American legislation; it is not part of the agreement but was necessary in order to win Congressional approval.

There was plenty of controversy in Washington before Trump certified Iran’s compliance and the US interest in July; there is more in the lead-up to his decision on which way to go in October. There has been a report of pressure on US intelligence to find grounds for refusing to certify Iran’s compliance. Israeli Prime Minister Binyamin Netanyahu has joined Trump to stand against the JCPOA. The US columnist of the Financial Times is among those who see Trump’s UN address as a pre-announcement of US withdrawal from the agreement:

Here in a 4-minute film is my take on it; the super-summary is that the deal is sound, implementation is effective and opposition to it is not technical but political.

The IAEA says Iran is complying with the agreement. A raft of influential Europeans have come out in favour of continuing with the agreement. More strikingly, Haaretz reports that Israeli intelligence disagrees with Netanyahu about it (and, evidently, is willing for the disagreement to be public knowledge).

If the US President does state that Iran is not implementing the agreement and/or that the agreement is no longer in the US national security interest, Congress will have to decide how to react. It will probably but not inevitably go along with the President’s view. If it does, then it’s over to the other parties to the deal – the European Union and Russia, which support continuation of the agreement, and Iran. The latter stands by the agreement and is implementing it according to the IAEA, but President Rouhani has threatened to withdraw from it abruptly if the US keeps imposing new sanctions.

Abandoning or fatally undermining the JCPOA will not increase US national security. Neither Israel, nor the US nor any US ally in the area benefits if Iran is tempted back onto the nuclear path. Richard Haas, President of the US Council on Foreign Relations, recalls the “axis of evil” speech by President George W Bush in January 2002:

And that is, in itself, a source of nuclear temptation for Iran:

And more broadly, acting against the JCPOA sends a profoundly negative signal about the value of signing an agreement, especially one about nuclear technology.

The JCPOA was a good and important deal when it was signed. It is being implemented properly. When you go behind the headlines, there is a great deal of technical complexity in the Iran nuclear issues and the JCPOA itself. But this is one complex issue that is not actually very complex at all.