Theresa May may be regretting she issued such a swift invitation to Trump when she was one of the first to fly over to congratulate him in early 2017.

With many Conservative commentators and politicians openly contemptuous of him, showing Trump a decent level of hospitality is going to be difficult without criticism from many sections of British society across the political spectrum and accusations of spinelessness, including from the Tories, that could further corrode the prime minister’s authority.

The Mail on Sunday’s Dan Hodges called Trump “…..a racist, misogynist and agent of influence for a hostile foreign power that has attempted murder on the streets of the United Kingdom.”

Soon after Trump announced that right after visiting Britain and attending a NATO summit he will meet one of his idols, Russian dictator Vladimir Putin, the leader of the hostile power Hodges refers to. 

However, it is vital that Trump comes away from his visit to Britain able to pass it off to his supporters as a diplomatic triumph.

That is important not just for Britain’s future but for the entire economic and security structure of western democracies. 

At the disastrous June G7 meeting in Canada where Trump insulted fellow participants, deepened a trade war and lamented Moscow’s absence (banned for invading Ukraine and annexing Crimea in 2014) he particularly snarled relations with the German, French and Canadian leaders.

That has left May as probably the only significant Western leader who can still influence Trump and salvage something from the American president’s wrecking ball foreign policy which has endangered traditional alliances.

She will have to withstand a barrage of criticism from political enemies and to overcome any distaste of her own for Trump, with many of her friends appalled at his routine mendacity, bullying, adulterous dalliances with porn actresses, uninvited groping of women, tolerance of racists, fascists, crooks and admiration for nasty dictators – notably Putin. 

She will have to summon up skills of communication with the public, deemed lacking during the last parliamentary elections, to explain to the British people why she must be nice to Trump.

Britain depends enormously on trade ties with the US and as Brexit looms, their importance increases. On the positive side, when May visited him in Washington last year, Trump said that he wanted to increase those links once the UK was unencumbered by EU restrictions on bilateral trade deals outside the union.  

Another vital sphere of US-UK relations is defence. Even if May relents in the dispute with her own party and provides the larger defence budget the UK needs, Britain will still depend on the US to keep it in the top tier of military nations. This allows London to pack a hefty punch for its size on the international stage. That might prove useful when we exit the EU’s common foreign policy. 

The extent of US support isn’t widely known in Britain which, since the end of the Cold War, has considerably eroded its military capacity. 

An American Defense Department official told Reaction that when a British politician or senior military officer turns up at the Pentagon they know London is going  to ask for something – “We’re the gift that keeps giving”.  

The UK needs the US to base its F35 combat planes with US pilots aboard its two new giant Royal Navy aircraft carriers as Britain hasn’t got enough of its own planes. Britain receives many other “gifts” and bargain deals in terms of equipment, technology-sharing, training and cooperation from the US.

On the other side of the equation Britain is rightly treated generously, even affectionately, by the US because the UK, unlike most other American allies, has supported the US in its conflicts except Vietnam. Britain has earned the right to special treatment by Washington through the sacrifices and lives of its military fighting alongside its US ally.

Britain is also a key member of the American-led intelligence gathering and sharing quintet involving Canada, Australia and New Zealand. 

These factors, along with Britain’s excellent abilities to impress those who like pomp and fanfare – as Trump obviously does – all add up to a strong hand for May.

If exploited skillfully she stands a fair chance to persuade Trump to back away from an all-out trade war but to resist blowing up the NATO summit the way he did the G7 conference.

May will also have one of the final opportunities to sway Trump, ahead of his meeting with Putin, not to give too much away in his eagerness to please Russia’s criminal strongman.

That is going to be tricky as many are unclear about why Trump is so keen on buddying up with Putin.  Although much has emerged from the investigation  by special counsel Robert Mueller into Trump’s Russian connections that points to business dealings that resemble money-laundering.

Such connections could make him susceptible to blackmail by Moscow and hence pliable to the Kremlin’s wishes although Trump will justify his coziness with Putin with platitudes about the need to reduce tension with a nuclear-armed Russia. 

May will have to be resourceful in making a case for Trump not to forgive Putin for all the immense harm he has caused to the US or to eliminate sanctions for Moscow invading and waging war on Ukraine, poisoning people on UK soil, tolerating or assisting in the use of chemical weapons in Syria, and using “hybrid warfare” to distort and undermine the very notion of truth in the news and information sphere.

On a juvenile, emotional level Trump craves Britain’s approval much more than that of France, Germany, Japan and the other major Western states because even he is aware of a “special relationship” between the UK and US which has been forged by war and mutual shared culture. English is the only language he has at least partially mastered. And he likes to boast about his Scottish roots and golf club. He also knows that a huge number of Americans, likely a majority, including his own “core” supporters, admire much about Britain.

Although most of those opposed to welcoming Trump are completely genuine in their criticism some such as Labour leader Jeremy Corbyn and his Stalin-admiring propaganda chief, Seaumas Milne, will criticise her hosting Trump from a position of utter amoral cynicism.  

They are the type of diehard, lefty leaders who have seamlessly transferred apologist allegiance from a Communist Kremlin to its current fascistic iteration. 

She should remind everyone how they tried to shield Putin from accusations over the nerve agent and ask how they reconcile their defense of Putin with his support for Trump.

Trump will pass but Britain needs the goodwill of the US over these turbulent and dangerous years.  This is also an opportunity for London to demonstrate to an often scornful, perhaps even spiteful Brussels, that even outside the union Britain has an invaluable role to play as a bridge in relations with Washington.

The message for ordinary British people concerned at the morality of welcoming Trump is that the UK has, out of necessity, played a courteous host to many other odious visitors without staining its honour and on this occasion too Mrs May must close her eyes, lie back and think of England… the UK, the EU and the Western world.