It was a well-staged play between great powers, or more precisely, a play where medium-sized and large powers meet.
In a brief video released from 10 Downing Street on Saturday, British Prime Minister Keir Starmer leaned into a speakerphone as a White House operator said: “You're now connected to Air Force One.”
“Congratulations, Prime Minister,” said Biden, who was on his way to Wisconsin for a campaign rally. “What a win!”
The two leaders spoke passionately about the importance of the UK's “special relationship” with the US, their shared commitment to defending Ukraine and their upcoming talks. Starmer leaves for Washington on Tuesday, where Biden will host a NATO summit.
Not since President Barack Obama's first term have both the White House and Downing Street been in the hands of a centre-left party. After years of tension over Brexit, Northern Ireland and disappointment over Britain's trade deals, this could herald a new era of harmony in transatlantic relations.
It may also be a short one: Four months from now, U.S. elections could return to the presidency a man who has had a fractious relationship not only with the center-left but also with the center-right leader of the United Kingdom, Prime Minister Theresa May.
Diplomats and analysts say managing Britain's relationship with one of its closest allies at a time of great uncertainty will be a delicate challenge for Starmer, who faces the threat of a Democratic president who finds himself on the defensive even within his own party and a Republican successor who disagrees with him on core issues from Ukraine to climate change.
A landslide Labour victory would normally be good news for Biden. British voters tend to foreshadow political change in the U.S., like the election of Margaret Thatcher a year before Ronald Reagan, or the 2016 Brexit vote five months before President Trump's election.
But while Starmer's victory was overwhelming, there were some issues, including the strong showing of Reform Britain, an anti-immigration reform party led by Nigel Farage, a staunch Trump supporter. Biden also has his own problems, not related to the political cycle but to actuarial tables.
“It's going to be important for the administration to hedge against who the Democratic nominee is, whether Donald Trump wins and what U.S. policy will be regardless of who wins,” said Leslie Binjamuri, director of the United States and Americas program at British research institute Chatham House.
Starmer will also have to decide issues such as how to respond to the outcome of the US election, she said, especially if it turns out narrowly against Trump. When Israeli Prime Minister Benjamin Netanyahu congratulated Biden on his 2020 victory — an outcome Trump continues to contest without evidence — Trump responded angrily, fuelling resentment toward Netanyahu.
Given that scenario, diplomats will want to focus on what Starmer can achieve with Biden over the next six and a half months, with the two men agreeing on issues such as military aid to Ukraine, aggressive government action to curb climate change and strengthening Britain's ties with the European Union.
Analysts say that last bit could be a game changer, given that transatlantic tensions over Brexit have been building since before the Brexit referendum, when President Obama famously warned Britons that they would be “in the back of the queue” for trade deals if they voted to leave the EU.
“Political relations have been strained since the UK's decision to leave the EU, particularly because Brexit poses risks to the smooth implementation of the Good Friday Agreement in Northern Ireland,” said David Manning, the last ambassador to the US under Labour Prime Minister Tony Blair, the 1998 deal that ended decades of sectarian violence in Northern Ireland.
“This is a chance for a fresh start,” he said.
Starmer will be accompanied by Foreign Secretary David Lammy, a Harvard Law School alumnus and close friend of President Obama. Neither he nor Starmer have high hopes for a trade deal, given the Biden administration's lack of interest in one.
But Starmer could ease lingering tensions over Northern Ireland, which is embroiled in often hostile negotiations with the EU over the terms of Britain's departure from the bloc.
The issue has irked Biden, who is proud of his Irish descent, and has frequently warned successive British governments against taking any action that would jeopardize the Good Friday Agreement.
Visiting Belfast for the first time since becoming prime minister on Monday, Starmer said a Labour victory would mark a reset for Northern Ireland and promised a “respectful and collaborative” relationship.
Mary Lou McDonald, leader of the Irish nationalist party Sinn Féin, said the difference between how Labour and the Conservatives responded to the government was like “night and day”.
Tensions over Northern Ireland had eased somewhat under Mr Starmer's predecessor, Rishi Sunak, who agreed a Northern Ireland trade deal with the European Union last year.
Analysts say issues such as trade ties with China could be a bigger source of tension, as the Biden administration presses Britain and other allies to take a more combative approach.
“The UK needs economic growth,” Binjamuri said. “Choosing between the US and China is not a good position for the UK.”
Analysts say that if Trump wins a second term, he won't care about Northern Ireland but will likely be put off by Starmer's efforts to draw him closer to Europe. The only other prime minister Trump has had a warm relationship with is Boris Johnson, whose willingness to clash with the European Union has superficially mirrored the president's own populism.
That's not to say that leaders of opposing parties in the UK and the US can't work together. After all, Mr Obama threatened Blair against leaving the EU at the request of Conservative Prime Minister David Cameron, who called for a referendum but opposed Brexit. And Mr Blair famously supported George W. Bush's war in Iraq, to ​​the point that Mr Bush relied on him to negotiate with other leaders on his behalf.
“Mr Bush thought it would be useful to gauge the temperature difference with Mr Blair,” Manning said. “It's hard to imagine that Mr Trump wants that kind of relationship, but a lot will depend on how he approaches America's traditional transatlantic partners.”
