Joe Biden’s promise that the US is back on the world stage as an advocate of multilateralism holds huge opportunities for the UK so long as it steps up a gear diplomatically, uses its presidency of the G7 well and shifts its stance in the Middle East. In the short term, Biden’s promise to end support for offensive operations in Yemen has led to calls for the UK to suspend its arms sales to Saudi Arabia, including from the Conservative chair of the defence select committee, Tobias Ellwood, and the shadow foreign secretary, Lisa Nandy. The devil will be in the detail as to what the US means by offensive, as opposed to defensive operations, but at the very least, the Biden decision, accompanied by the appointment of a new special envoy is an implied rebuke to the way in which diplomacy to end the conflict had ground to a near halt. The UK is the penholder on Yemen at the UN and the UN special envoy for Yemen, Marin Griffiths, is British, but simply to blame UK lethargy or Saudi intransigence solely for the failure to make progress on Yemen is to underestimate the difficulties diplomats have faced in bringing the many sides, including the Houthi rebels,to the negotiating table. Saudi Arabia may be deemed the culprit in initially intervening in a civil war in March 2015 that they thought would only take months to end after the Houthis had captured the capital, Sana’a. But the consensus is now that Riyadh would like the war to be brought to a close, and a power sharing government formed. The large number of missiles hurled across the border to Saudi Arabia by the Houthi forces however makes that harder. It remains to be seen if the US regards the Yemen civil war as a compartmentalised problem, or part of a wider rethink of US support for Saudi Arabia and the United Arab Emirates, part of the Saudi-led coalition. One test will be whether the administration sticks by its pledge to reveal its intelligence on the murder of the Washington Post journalist Jamal Khashoggi in Saudi Arabia’s Ankara consulate. New governments start with big ambitions, and if the US could bring Saudi Arabia and Iran together to end their near 40-year race to the bottom that would be seismic. But much will depend on whether the Europeans, including the British, can help the US find a way back into the nuclear deal that Donald Trump left, and then into a wider discussion about Iran’s relations with its neighbours. The current forecasts in European capitals are gloomy, and Biden made no mention of Iran in his speech. Britain will however be delighted that Biden moved so clearly on Russia, set out a balanced approach to China and committed himself so forcefully on the climate crisis. The good fortune of the UK’s presidency of the G7 presents a lot of low hanging fruit on which the US and the UK can jointly graze. It is already noticeable that the UK is being hyperactive in organising joint G7 statements on issues such as the arrest of Alexei Navalny and the Myanmar coup. After a year in which the G7 under Trump was largely invisible, the UK can act as handmaiden to the return of multilateralism. Giving evidence to the defence select committee this week, Sir Kim Darroch the former UK ambassador, argued that the UK also now has specific policy opportunities. “Out of the EU it will be more straightforward for the UK to align with the US on Russia because there is always a temptation for Europeans to edge towards a more equidistant position between the US and Russia,” he suggested. Germany continued support for the Nord Stream 2 gas pipeline, now opposed in the US, UK and France, looks vulnerable Equally on China, Biden gave a clear steer to Britain that he is not proposing in a full decoupling. Darroch summed it up: “We need to balance our need to challenge China on its trade practices, its military activities in the South China Sea and its human rights record, and wanting it as a partner on climate change. Getting those two working together is going to be a huge challenge”. He could have added the challenge is made harder given the strong anti-China mood on the backbenches. But it will not just be about policy; it will also be about commitment and style. In a Policy Exchange pamphlet this week, Ben Judah claimed the Washington embassy had been run down, and the UK was suffering an elite opinion crisis in the US. Judah said the Democrats view British influence as in a Brexit-induced decline and he partly laid this at the door of the British embassy’s communications strategy, At the defence select committee, Lord Darroch hit back, saying perceptions of Britain would largely depend on its economic performance. He also derided the advice he used to receive as ambassador. “We were getting almost daily communications advice from London on what we should be saying, mostly centred on the line ‘Brexit means Brexit’, and ‘Tell them that we will win the next meaningful vote’. “I and the embassy tried – I promise – exceptionally hard to present as positive a picture as possible, but against this background, it was, to understate matters, an uphill task. I think the idea that a different communications strategy would have turned this around and made the UK look great is, frankly, a bit of a fantasy.” But all sides seem to accept this is a turning point for Britain’s bilateral relationship. The US will lose Britain’s influence around the EU table, diminishing the breadth of the relationship, but that just requires the UK to work even harder to make itself useful to the US. The opportunity and the machinery is there, but it depends on a British political leadership to realise this.