When Donald Trump took the oath of office, less than 11 months ago, the word of the hour was normalisation. Let’s not treat this man like a normal president, his US opponents said, because he’s not. You can’t, for example, assume that most of what he or his White House says is the truth – as you would for a normal occupant of that office – because he is a serial and proven liar. And sometimes it will not be enough to describe his words or deeds as “controversial” or “racially charged”, because the right word will be “racist”.

For most of the past year, that normalisation debate has raged chiefly inside the US. But now it is a global question. Put simply, how should the peoples of the world handle Donald Trump?

Trump's Twitter attack only serves to increase UK's post-Brexit angst | Patrick Wintour Read more

That question has pressed in on Britain particularly sharply this week, after Trump retweeted three inflammatory and unverified anti-Muslim videos shared by the deputy leader of the Britain First group, a faction of the far right so far off the spectrum that an unfamiliar chorus of voices united to condemn the president for legitimising its message. Even Nigel Farage and the conspiracy-theorist headbangers of America’s Infowars website could not defend him.

One can raise a quizzical eyebrow at those my colleague Marina Hyde calls the “nouveau woke”, asking what took these new critics so long. It’s not as if Trump had carefully concealed his bigotry until now. In August, he declared that white supremacists marching in Charlottesville with swastika banners and in the robes of the Ku Klux Klan included “some very fine people”. And in January – just a few hours after he had grasped Theresa May’s hand at the White House – Trump signed an executive order banning arrivals from seven proscribed countries, each with a Muslim majority.

But for Britons, his tweets this week struck closer to home: not content with demonising non-whites in his own country he was now promoting a group hellbent on spreading fear and loathing in ours. In the process, and by angering those who had previously kept silent, Trump brought a rare degree of unity to these fractured islands.

Play Video 1:27 Retweeting from Britain First was the wrong thing to do, says May – video

The focus now is on May’s invitation to Trump to come to Britain on a state visit. You will recall she made that offer – usually extended only late in a presidency – on that lightning trip to Washington, when the prime minister thought it would be smart to be the first foreign leader to visit the new president, and to come bearing extravagant gifts. How she must regret that move now: Trump can’t possibly be given the red carpet, gold-coach-on-the-Mall treatment, not in the current climate.

But to rescind an invitation – one that officially comes from the Queen – would be an enormous insult that would only escalate tensions further. So May must hope the current state of limbo will persist indefinitely: the invitation will remain suspended in the air, as the Americans avoid setting a date for fear that, were Trump to come, he would be humiliated by the sight of 65 million Brits giving him a two-fingered salute.

Still, the very fact that this ludicrous situation even exists points to a larger problem: the absurdity that is the so-called special relationship.

So-called because it’s only the Brits who call it that. The Americans never use the phrase unprompted. When they do, it’s only out of an embarrassed obligation to accommodate British neediness. A former state department official, Jeremy Shapiro, admitted in October that his bosses were always careful to use the phrase when the Brits were in town, “but really we laughed about it behind the scenes”.

It was the driving spirit behind Tony Blair’s catastrophic decision to support the US-led invasion of Iraq in 2003

And yet it matters to us desperately – and the Americans can smell our desperation. How much time does a visiting British prime minister get with the president? What kind of gift do they hand over? Is the body language warm or chilly? All these questions have obsessed the political class, policymakers and journalists alike, for decades. But this is not diplomacy: it’s neurosis.

Perhaps one could laugh off this behaviour, dismissing as mere pathos the notion of a country that thinks it alone has a special relationship with Washington, unaware that a 2009 study found that 14 of 25 EU nations surveyed all believed they too were special to the Americans. But this fetish has real-world consequences.

It was the driving spirit behind Tony Blair’s catastrophic decision to support the US-led invasion of Iraq in 2003. Blair’s judgment was that the paramount strategic objective was to be at Washington’s side: “With you, whatever.” All other considerations were subordinate to that goal.

That same urge propelled May to visit Trump in Washington too soon, where she “put her career, her reputation and the national interest in the hands of someone who can land almost anywhere on any topic and be on the opposite side the very next day”, says Mark Leonard, director of the European Council on Foreign Relations.

We are, says Leonard, over-invested emotionally in the fantasy we call the special relationship. Yes, there is shared history; and, yes, intelligence and special forces cooperation is intensely close. But for the rest, we need to end the neurotic neediness – and be a bit more like the French.

It’s striking that Emmanuel Macron has managed both to host Trump in Paris and to stand up to him on, say, climate change, with a minimum of psychodrama. Indeed, the US president is said to like his French counterpart a lot. Part of that will be personal: a misogynist like Trump was bound to show more respect to a man than to May (or, for that matter, Angela Merkel, whose hand he famously refused to shake).

Trump retweeted anti-Muslim videos to 'elevate the conversation', White House claims Read more

But it’s also true that France has long managed to be more detached than Britain in its dealings with the US. Paris decides what it wants to achieve in the world, and either works with or against Washington, depending on what best serves its interests. So while Blair followed George W Bush to Baghdad, Jacques Chirac had no hesitation in staying well out of it. For Robin Niblett, director of Chatham House, it’s clear we need to ditch the sentimental guff and “be more hard-nosed”.

Hold on, say the Brexiteers. Maybe there was a time when we could have loosened our links to the US, but not now: once we’ve left the EU, they say, we will need the US as a partner in a new free trade agreement.

Even if you buy that logic, Trump is the wrong man to rely on. We know he regards free trade as a con: the only good deal, he once wrote, is one in which “you crush the opponent and come away with something better for yourself”. As a matter of principle, he doesn’t believe in win-win. He is a zero-sum merchant – and he will make sure Britain gets zero.

Besides, Friday’s guilty plea in the Russia inquiry by the former national security adviser Michael Flynn suggests the net is beginning to tighten on Trump: by the time post-Brexit Britain is ready to talk trade with Washington, he may not even be there.

So now, at the end of this first year of Trump, is the ideal time to ditch our delusions. If Britain is to be a grownup country, with a measure of self-respect, the time has come to look at the US with clear eyes – and to treat it as an ally whose leaders change. Sometimes those leaders will reflect our values and interests; sometimes they will clash with them; and, very occasionally, they will actively undermine them. When that happens, we have to be ready to stand up for ourselves and against Washington. Now is one of those moments.

• Jonathan Freedland is a Guardian columnist