Thank goodness Donald Trump isn’t the kind of President-elect who mocks the afflicted, or you might worry about the tweet he shared with his 19.4m loyal followers on Sunday. “I look very much forward to meeting Prime Minister Theresa May in Washington in the Spring. Britain, a longtime US ally, is very special!” Despite the clunking “look very much forward” (Finnish au pair; third night away from Helsinki), translating the first sentence is the easy bit. What I suspect he meant was “Ach, that prissy English broad is coming over, and I’ll have to waste a few hours pretending to listen to her begging. #limeylosers” It’s the second sentence that looks ambiguous. Was Trump referencing the most tedious cliche in the diplomatic handbook? Or did he use “special”, as people used to do, as a euphemism for severe learning difficulties?

The hint is in the exclamation mark. It makes me hear the words in the voice of an Alan Bennett granny proudly telling her friend, Ida, about a grandson. “He’ll never get a GCSE, of course. The teacher says he’s very special!”

If that’s how Trump did mean it, who could argue? In geopolitical terms, Brexiting Britain is the one making the macrame pot plant holders at the back of the remedial class next to Zimbabwe. No one could doubt that, in an Anglo-American context, we have special needs. We need the United States’s indulgence – and especially a trade deal.

Trumped! The best cartoons on 'The Donald' Show all 28 1 /28 Trumped! The best cartoons on 'The Donald' Trumped! The best cartoons on 'The Donald' Brian Adcock Trumped! The best cartoons on 'The Donald' Dave Brown Trumped! The best cartoons on 'The Donald' Brian Adcock Trumped! The best cartoons on 'The Donald' Dave Brown Trumped! The best cartoons on 'The Donald' Dave Brown Trumped! The best cartoons on 'The Donald' Brian Adcock Trumped! The best cartoons on 'The Donald' Dave Brown Trumped! The best cartoons on 'The Donald' Dave Brown Trumped! The best cartoons on 'The Donald' Dave Brown Trumped! The best cartoons on 'The Donald' Brian Adcock Trumped! The best cartoons on 'The Donald' Dave Brown Trumped! The best cartoons on 'The Donald' Brian Adcock Trumped! The best cartoons on 'The Donald' Dave Brown Trumped! The best cartoons on 'The Donald' Brian Adcock Trumped! The best cartoons on 'The Donald' Dave Brown Trumped! The best cartoons on 'The Donald' Brian Adcock Trumped! The best cartoons on 'The Donald' Dave Brown Trumped! The best cartoons on 'The Donald' Brian Adcock Trumped! The best cartoons on 'The Donald' Brian Adcock Trumped! The best cartoons on 'The Donald' Christian Adams for Daily Telegraph Trumped! The best cartoons on 'The Donald' Martin Rowson for The Guardian Trumped! The best cartoons on 'The Donald' Christian Adams for Daily Telegraph Trumped! The best cartoons on 'The Donald' Morten Morland for The Times Trumped! The best cartoons on 'The Donald' Bob Moran for Daily Telegraph Trumped! The best cartoons on 'The Donald' Christian Adams for Daily Telegraph Trumped! The best cartoons on 'The Donald' Morten Morland for The Times Trumped! The best cartoons on 'The Donald' KAL for The Economist Trumped! The best cartoons on 'The Donald' Martin Rowson for The Guardian

When we might get one is anyone’s guess, and Boris Johnson’s is suitably vague. “We hear that we are first in line,” the Foreign Secretary bullishly declared during a supposedly “secret” trip to New York, “to do a great free trade deal with the United States.”

Is that what we hear? And if so, from whom? Not from Trump himself, who couldn’t find spare the time to allow Boris an audience. That seems a shame when these two have so much in common. Both are native New Yorkers with more affection for extramarital activities than paying their taxes. At one point, Boris planned to renounce his American passport to avoid the income tax the US levies on all citizens, wherever in the world they live and work. But for some reason – possibly the realisation that anyone with doolally hair and a TV profile can make it to the Oval Office – he seemed to renege on that last year.

And both have shown, or are suspected to have shown, a taste for odious racial nomenclature. Footage of Trump using the “n” word in The Apprentice hasn’t surfaced yet, but Boris famously included the Edwardian elegance “picaninnies” in a bylined article.

Another thing they share is a talent, apparently modelled on Shaggy’s hit single “It Wasn’t Me”, for brazenly denying the obvious truth, be it Trump’s taunting of a reporter’s disability about which Meryl Streep emoted at the Golden Globes, or Boris’s “inverted pyramid of piffle” about accurate coital allegations. Had they met in New York, Boris would no doubt have assured his host that he never called Trump “unfit for office”, “clearly out of his mind”, and guilty of “stupefying ignorance”.

Boris Johnson sends out Christmas message

But they didn’t meet. Instead, Boris was palmed off with Jared Kushner, Trump’s son-in-law and future senior advisor, among other assorted Republicans. Presumably Kushner was the source of the joyous announcement that Britain – far from being at the back of a 10-year long queue, as Obama warned – will be first in the trade-deal line.

What could such a guarantee possibly be worth? Even if Kushner knows Trump’s mind better than most, that mind appears to change every three and a half minutes. Besides, at least in this one narrow area, Trump will be a tediously conventional US president: he will prioritise only what is in his interests.

Unless the Government bribes him with St Andrew’s, Turnberry and five other Open-hosting golf courses, striking a trade deal with Britain will not be high on his presidential bucket list. The UK-US balance of trade is approximately neutral (we export about as much as we import), but US GDP is about eight times Britain’s and a trade deal means correspondingly less to their economy than to ours.

Even if Trump wanted to be nice (ha ha ha), negotiations cannot start until Britain leaves the EU customs union in 2019 at the earliest. Given that US trade deals with small countries take an average of almost four years, nothing could be signed until the middle of – may God forgive me for typing such words – Trump’s second term.

You can’t really blame Boris for taking refuge in fantasy. All who are trapped in the Bizarro World of Trumpland seek solace where we may. But in conflating a casual remark from a Trump flunky with a serious commitment, he betrays a weakness for mindless consolation once again. In 2013, when asked what song he wanted played at his funeral, the then London Mayor responded by singing Bob Marley’s “Three Little Birds”. “Don’t worry about a thing,” goes the chorus, “Cos every little thing, is gonna be all right.”

It isn’t, of course; much less every big thing like a swift and favourable US trade deal. Still, credit where it’s due. Boris sang it so tunefully that, if he offered to reprise it, he’d be snapped up as the headline act at Trump’s inauguration.