Starmer has the backing of Britons to stand up to Trumpism. At the White House, he should do so | Polly Toynbee

Day by day another vast hole opens up beneath what was once solid. The man who is on course to become Germany’s next chancellor, Friedrich Merz, once the most pro-US of leaders, has declared Nato in effect over. In his clear-eyed perception of Donald Trump’s first month, 80 years of shared transatlantic values have fallen into that crater. The US “doesn’t care about the fate of Europe one way or another” and Washington’s actions have been “no less drastic, dramatic, and ultimately no less brazen” than Moscow’s, he said. Now, Europe must defend itself.

The moment smacks of that 1940 David Low cartoon of a British soldier standing on a rock in a stormy sea, shaking his fist as the Luftwaffe approach: “Very well, alone”. But this time we Europeans are alone. JD Vance, the US vice-president, declared war on European values and traditions; Europe’s liberal “enemies within” are more dangerous in his eyes than Russia or China. Those spell-breaking words told Europeans that the US can never be trusted again; at any time, Americans may vote for a leader who betrays old allies, sharing no affinity with Europe’s liberal democracies, international rights or laws. “The west” no longer exists as an entity bound by shared beliefs.

Keir Starmer knows that every step he takes inside the White House on Thursday could set off some Trumpian explosive device. Emmanuel Macron will have already tested the ground (he arrived there today). The US president’s wild unpredictability, whether by design, delusion or distraction, is a weapon in itself, and a wary Starmer is war-gaming it with his advisers. That “bridge” of a “special relationship” remains in No 10’s official briefing lexicon, but by now it is wholly illusory.

David Low’s June 1940 Evening Standard cartoon Very well, alone. Illustration: Pictorial Press Ltd/Alamy

Starmer’s task is to salvage the best possible agreements on Ukraine, tariffs and defence without wavering on what once were mutual principles. He has his red lines, echoed across Europe: “No talks about Ukraine, without Ukraine”. No mafioso protection racket grabbing Ukraine’s mineral wealth to pay off bogus debts. Reuters reports that unless Volodymyr Zelenskyy pays half a trillion dollars, the US will cut off Ukraine’s access to Starlink, Elon Musk’s satellite communications network, crippling the country’s defences. In the face of such brutishness, Starmer is the right man: lawyerly, calm and diplomatic. He will not be riled into pointless verbal warfare. He brings Europe’s pledges to spend more, and possibly the hubristic offer of the UK’s new ambassador, Peter Mandelson, of a “new economic partnership” with the UK as a hub for US AI to “Make our economies great again”.

But everyone can see that Trump’s “reset” with Vladimir Putin is irreconcilable with Nato. The alliance is dead if it fails to resist a Russian aggressor, a despot who murders opposition politicians, commits unspeakable war crimes, kidnaps thousands of Ukrainian children, with a declared intent to return Warsaw pact countries to its embrace. Trump is Russia’s greatest asset.

Starmer will avoid verbal spats with a champion spitter. Be bold, comes the best advice from Merz, warning Europe’s leaders “not to come to Washington as a dwarf” or they “will be treated as one”. As Europe speedily circles the wagons, the UK finds its role will be vital, as Macron and Merz call for a joint nuclear shield to be provided by France and the UK, pivoting from US nuclear dependence. In a continent that is losing the security we relied on all our lives, trade disputes become a trivial quibble, Brexit an irrelevance. Merz is calling for Europe to come together in foreign, trade and security policy. Starmer ought to seize the chance, and abandon Labour’s fears of Brexiters.

With its colossal majority, Labour has nothing to fear in rallying the country around joint European defence as a necessary patriotic cause, leaving the Tories and Reform confounded. The public that welcomed Ukrainians rejects Trump’s betrayal plans: 21% of people strongly support British soldiers being stationed in Ukraine as peacekeepers, and 37% of people “somewhat” support the idea. Only 21% are opposed to it. The idea of a European army would have been unthinkable during the Brexit referendum. Meanwhile, on trade, a majority of voters in every constituency thinks the government should prioritise trade with the EU over the US, even in Clacton, Nigel Farage’s seat.

Fifty-five per cent of Britons now say it was wrong to leave the EU, while just 11% call Brexit a success. There’s no need to reopen those old wounds. A Europe united against new perils seems likely to loosen its rigid single market rules on trade, given that Britain would be contributing so much in mutual defence. As Britain strives to spend up to 3% compared with Germany’s 1.5% defence spending, the doors to trade must surely open for the UK to regain some of the 4-5% of GDP it has lost since Brexit.

Hugh Grant and Billy Bob Thornton in Love Actually, 2003. Photograph: Landmark Media/Alamy

The Brexiters now sound bizarrely out of tune. Last week, David Frost, who led the UK’s negotiations with the EU, frantically tweeted: “Labour are taking us back into the EU orbit by stealth and hoping you won’t notice till it’s too late. Don’t let them get away with it.” Yet those days are done. Instead, all of Europe and the UK need defence eurobonds for all to borrow. If the opposition attacks the chancellor for breaking a borrowing pledge, Labour need only point to the frightening new world where Elon Musk sends warm congratulations not to Germany’s new leader, but to the far-right AfD.

There will be a White House press conference during Starmer’s visit, a dangerous opportunity for Trump to say unspeakable things while leaving Starmer dumbstruck. If he’s lost for words, he might remember those spoken by a particularly memorable British prime minister at a press conference with a US president in 2003. Hugh Grant, playing the prime minister in Love Actually, told the president, Billy Bob Thornton: “I fear that this has become a bad relationship; a relationship based on the president taking exactly what he wants and casually ignoring all those things that really matter to Britain. We may be a small country, but we’re a great one, too … And a friend who bullies us is no longer a friend. And since bullies only respond to strength, from now onward I will be prepared to be much stronger. And the president should be prepared for that.”

The real world is not scripted by Richard Curtis for happy endings. Poking presidents in public is not politic, and Starmer is likely to offer Trump a carriage ride with King Charles. But he will have no trouble rousing voters to defend European and British values against Trumpism.

• Polly Toynbee is a Guardian columnist

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