The measured presence of Joe Biden in the White House, vacated gracelessly by the geopolitical arsonist Donald Trump, may be having a mildly calming effect on the Middle East, the most reliably combustible region in the world and perennial provider of what the US has come to think of as “forever wars”.

A US delegation, headed by Robert Malley, the special envoy for Iran, is trying to resurrect the 2015 nuclear accord that Iran signed with Barack Obama’s administration and five other world powers, but from which Trump unilaterally withdrew in 2018. Indirect talks in Vienna — where other signatories to the accord shuttle between Americans and Iranians — have sparked hope of at least an interim deal.

Meanwhile, as the Financial Times revealed last weekend, Iran and Saudi Arabia, arch-rivals for hegemony in the Gulf and the region, have been holding talks in Baghdad to try to patch up what is also a Sunni-Shia schism poisoning the Muslim world. These talks may be exploratory. But they reach across a sectarian divide between rival theocracies that lie on opposite sides of a chain of ruinous proxy wars: the Wahhabi fundamentalist Sunni kingdom of the Saudis, and the Shia supremacist Islamic Republic of Iran.

Taken together, this dancing with detente by the US, Saudi Arabia and Iran would be almost balletic — except it is not clear there is a master choreographer.

That much is obvious from Israel’s flagrant efforts to sabotage Biden’s nuclear diplomacy. Israel’s campaign of air and drone strikes against Iranian assets and proxies in Syria, Lebanon and Iraq — plus assassinations of nuclear physicists and attacks on nuclear facilities inside Iran — is guaranteed to ensure Tehran does not renounce its paramilitary formula of militias with missiles.

Israel’s “shadow war” emerged into blinding light this month with a sabotage attack at Natanz, Iran’s main uranium enrichment facility. The strike came as talks in Vienna approached the terms of Tehran coming back into compliance with the 2015 deal.

That deal restricted Iran, under international monitoring, to enriching uranium to 3.67 per cent of fissile purity. In response to Trump, Iran raised the purity level to 20 per cent. In reprisal for the Natanz attack, it then raised it to 60 per cent. That is a big step towards the 90 per cent purity of weapons-grade nuclear fuel.

Tehran says this is to show its ability to bounce back, as well as its mastery of the nuclear cycle, which it regards as a deterrent against nuclear-armed Israel. It has also said the 60 per cent level is reversible. Intriguingly, whereas the Natanz attack was underground, the high enrichment is being done above-ground — as though to provoke Israeli premier Benjamin Netanyahu to shoot his bolt with an air strike and challenge Israel’s US patron to restrain him.

President Biden regards Netanyahu with a suspicion born of long acquaintance. He is also hostile towards Mohammed bin Salman, crown prince and de facto ruler of Saudi Arabia. But the brash young Saudi heir-apparent has nothing like Netanyahu’s support in the US Congress, and that may be why he is exploring an alternative approach to Israel’s confrontation with Iran.

A straw in the wind came in an op-ed published in January by Abdulaziz Sager and Hossein Mousavian, well-plugged-in figures on the Saudi and Iran sides respectively. They argue for co-operation that addresses both countries’ security concerns, as these talks are starting to do.

In 2017, Crown Prince Mohammed responded to President Trump’s incitement by blustering threats to carry the region’s proxy wars directly into Iran. Two years later, though, he started changing his tune.

In September 2019, Iran carried out a devastating missile and drone attack on Abqaiq, oil processing hub of Saudi Aramco, the state oil company. In so doing, Tehran put on public display the kingdom’s vulnerability.

The Saudis have spent billions on US Patriot air defence batteries but, even though the attack came in two waves 34 minutes apart, senior Arab officials say, Riyadh had no response. Worse still, Abqaiq showed the US to be an unreliable security shield. Trump bragged that the US was “locked and loaded” but soon concluded it was Saudis not Americans that had been attacked.

Prince Mohammed has since dallied with Netanyahu and the idea of Saudi normalisation with Israel. Now he seems to be concentrating more on serial expiatory offerings to Biden, including ending a three-year blockade of Qatar, a maverick Gulf emirate but an important US ally.

Biden’s attempt at a reset with Iran remains very difficult. But any Saudi move to explore geopolitical competition with Iran rather than confrontation helps — even as a straw in the wind.