Kevin Lamarque / Reuters

The British national story goes like this: Here is the country whose empire once spanned the globe, and whose plucky citizens stood up to the Nazis—several years before the United States deigned to get involved in the Second World War.

That mythology has been hugely useful to supporters of Britain’s withdrawal from the European Union. Freed from the shackles of the EU, these Brexiteers argue, the country can once again assume its rightful leading role on the world stage.

But that argument comes with an asterisk, one that has been exposed by the resignation of Kim Darroch, Britain’s ambassador to Washington. In the future, Britain will not be dictated to by foreign powers—except the United States. Yeah, those guys can tell us what to do.

It is a high-risk strategy. Having stoked a mood of triumphant self-reliance, pro-Brexit politicians will find it hard to carve out an exception for the United States. This is why there is more to the Darroch affair than another Twitter tantrum from Donald Trump. After confidential assessments of the U.S. president as “inept” and “insecure” were leaked to Britain’s Mail on Sunday newspaper, Trump retaliated by tweeting that his administration would no longer deal with Darroch.

Boris Johnson, the front-runner in the race to replace Theresa May as prime minister, last night refused to support Darroch when asked about the issue in a televised debate with his challenger for the premiership, Jeremy Hunt. That prompted the ambassador’s resignation today. Darroch was probably doomed from the moment Trump first tweeted; an ambassador is useless without access to his or her host country’s government. But it is still remarkable that Johnson, a former foreign secretary, did not offer even token resistance to the U.S. president’s outburst.

By contrast, Hunt, the current foreign secretary and no one’s idea of a hotheaded blabbermouth, called Trump’s comments “disrespectful and wrong to our prime minister and my country.” Standing opposite Johnson, he promised to keep Darroch in his post. That earned him a round of applause. (Johnson’s comments, that the leaker should be “eviscerated,” were not as enthusiastically received.)

The row over Darroch comes at a crucial moment for Britain, which is due to leave the EU on October 31. For Johnson’s premiership to be deemed a success, he must not only take Britain out of the bloc, but also secure a trade deal with the U.S. soon afterward.

To do so requires massaging Trump’s ego, and this is where the chasm between the leading pro-Brexit politicians and the voting public becomes clear.

The 2016 Leave campaign painted the EU as a foreign power intent on dominating Britain. (Johnson himself once compared the EU’s aims to those of Hitler, while Hunt has since compared the bloc to the Soviets.) Like many Brexiteers, Johnson sees the U.S. more positively: as a buccaneering beacon of free markets compared with rules-obsessed Europe. But it might be hard to convince Leave voters to see it the same way. Britons have long bristled at the notion that their country is the junior partner in the “special relationship,” so why should a group that has been primed to see international alliances as humiliating now unquestioningly accept Britain’s subservient role?

Jingoism is also a potent force among Remainers when translated as standing up to American bullying. Their cultural touchstone is a scene from 2003’s Love Actually, where Hugh Grant’s prime minister stands up to the U.S. president, who has groped his love interest. “I fear that this has become a bad relationship,” he says. “We may be a small country, but we’re a great one too … Shakespeare, Churchill, the Beatles, Sean Connery, Harry Potter, David Beckham’s right foot, David Beckham’s left foot.”

To complicate things further, Trump is also personally unpopular in Britain. Only 21 percent of Britons have a positive opinion of the U.S. president, according to YouGov, while 67 percent have a negative one. (By comparison, 72 percent have a positive opinion of his predecessor, Barack Obama.)

In light of this, it’s not surprising that the debate audience responded so warmly to Hunt’s comments and so tepidly to Johnson’s. There is little demand among British voters for politicians to suck up to the United States. Unfortunately, that is exactly what Trump demands. He sees international diplomacy as a zero-sum game, where there can be only one winner. Autocrats can gain his respect, but cooperation is for the weak.

After Brexit, the British prime minister cannot alienate the thin-skinned U.S. president, but he cannot hug him close either, without repulsing his domestic audience. It will be a fine balancing act.

The resignation of Darroch encapsulates a strange political moment. A diplomat resigns for making observations that have been both widely reported and instantly vindicated by their subject’s response. Instead of backing a distinguished diplomat, the likely next prime minister equivocates, in the hope of appeasing the U.S. president. This plays badly with his domestic audience, but he considers the greater prize—a trade deal—to be worth it.

Arguably, this is realpolitik. But that ignores Trump’s nature. Some future slight might derail Britain’s hope of that trade deal. If he becomes the next prime minister, Johnson will undoubtedly be a better friend to the U.S. than to Europe. But it still might count for nothing.

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