The immediate and biggest foreign policy issue to confront the newly elected president of the Board of Deputies, Marie van der Zyl, is what, if anything, to do about Iran. Amid the final hustings that secured her election, Iran was barely mentioned as deputies worried about how to engage young people in board activities. Good luck with that. Older stagers will not readily ease their grip on office.

Iran is a huge issue. The recent rocket skirmishes at the Golan Heights (where Israel’s ‘iron dome’ defence system did its job) was an early signal of more to come. President Trump’s decision to abrogate the big power deal over Iran’s nuclear development opens a diplomatic chasm across the Atlantic.

Britain finds itself caught in the middle. It is an enthusiastic friend of Saudi Arabia which along with Israel is anxious to isolate the arc of Shi’ite Islamic extremism. It also wants to remain President Trump’s best friend. As the US is Britain’s single most important export market, forging a trade deal with America is critical to the UK’s post-Brexit future.

The UK was a party to the Geneva accords that brought Iran back into the global fold in 2015 and is potentially a beneficiary of the opening up of the Iranian market to the West; so it is conflicted. Should it follow the inclination of the Foreign Office and support multilateralism against Trump’s exceptionalism or should it align itself with the anti-Shi’ite axis? The Board of Deputies could well find itself caught in the middle of this struggle.

Some might ask what has any of this to do with British Jews involved in their own battles against anti-Semitism in the Labour Party. I would argue that it is of vital importance.

The lifting of financial sanctions against Iran allowed its coffers to fill again and the country’s ability to fund Hezbollah and other terrorist organisations across the globe was greatly enhanced. Hezbollah has used resources coming from Iran to build up formidable military installations along Israel’s northern border and tighten its grip on Lebanon. The decade-long Syrian civil war in which Hezbollah has been aligned with President Assad’s forces back means that this avowed enemy of Israel is more battle-ready than it has ever been. Only the recent Moscow handshake between Vladimir Putin and Benjamin Netanyahu offers the promise that Hezbollah temporarily can be restrained.

The value of the nuclear deal to Iran is largely economic. The collapse in the value of its currency, the riyal, and sharp rise in the price of Brent crude oil following Trump’s decision to revoke the nuclear accord, underlines how important it is to Iran’s prosperity.

Britain is critical in all this. When it comes to financial sanctions, all routes pass through London. As the world’s most important banking centre, it is all but impossible to be part of the global trading system and to obtain international credit without dealing with UK-based banks and financial institutions. A visit to the Treasury’s website illustrates this. It has an ever-lengthening list of Middle Eastern and Afghani entities proscribed because of sanctions or potential terrorist links.

The UK, Russia, France, China and Germany would like to find a way of keeping Iran boxed in as a nuclear power irrespective of America’s unilateral action. The US, Israel and Saudi Arabia do not trust Iran to discontinue development of ballistic systems and want to curb Iran’s support of terrorist networks.

Britain holds the key to the success of financial sanctions. It was rigorous sanctions which brought the apartheid regime in South Africa to its knees, ended Mugabe rule in Zimbabwe, brought Iran’s moderates to the negotiating table in 2014-15 and helped tame North Korea. The British Jewish community could play a critical role in encouraging the government to toughen its stand against Iran.

That will be a vital test of leadership.