Theresa May might have hoped that the decision to invite the US President to come to the UK on a state visit would win Britain a special place in the billionaire’s heart.

But the prospect of Mr Trump riding in a carriage with the Queen has awoken a special strain of outrage among swathes of the British public.

Royal officials may be preparing to roll out the red carpet for the former reality TV star but the invitation has sent a torrent of derision flying across the Atlantic towards the resident of the White House.

Demonstrators attend a rally in Westminster protesting against Donald Trump

More than 1.8 million people have signed a petition saying that although Trump should be allowed into the country he “should not be invited to make an official state visit because it would cause embarrassment to Her Majesty the Queen”.

This is what has riled of so many people. It is not just that they abhor his politics and his personality, there is dismay at the idea of the Queen being compelled to grant this honour to him for political purposes.

According to the Royal website, just two US presidents have come to the UK on official state visits since 1952 – the second Bush in 2003 (the same year that Russia’s Putin and his wife were honoured in this way) and Barack Obama in 2011.

George W Bush and Barack Obama are the only other presidents listed as having come on formal state visits

Reagan and Clinton enjoyed glittering welcomes to Britain but even their tours are not listed as official state visits. This makes it especially jarring for many that within days of Trump’s inauguration he received such an invitation.

It is clear why a state visit would appeal so much to Trump

Mr Trump astonished pundits was able to secure the presidency but it must irk him that Hillary Clinton won nearly 2.9 million more votes than him.

Both as a politician and as the former star of the Apprentice, he understands the importance of strong ratings, and a poor showing in the polls can only be grating.

Hillary Clinton beat Donald Trump in the total number of votes

He needs to forge a relationship with his wary electorate and cement his position as the US head of state. And what better way to do that than be filmed and photographed in the company of one of the world’s most respected heads of state?

For a nation that overthrew the forces of King George III, Americans retain astonishing levels of affection for the UK royal family. Trump himself has a taste for grandiose interior design and will relish the opportunity to take tea in Buckingham Palace.

And this is why Theresa May needs an ally in Trump

There are also clear reasons why Theresa May has worked so hard to forge a close relationship with the US President, even though her (literal) hand-holding with Trump is unlikely to win her many new votes.

President Donald Trump holds British Prime Minister Theresa May's hand as they walk along the colonnades of the White House

She is fighting to save the so-called special relationship as the UK scrambles to secure a route to post-Brexit prosperity.

Trump did not set out to woo the world when he hit the campaign trail. He defeated his Republican rivals and then Democrat candidate Hillary Clinton by preaching a message of America First that thrilled voters in the country’s rusting industrial heartland.

He did not tone down his populism in his inaugural address. He has pledged that the protection of US interests will be the guiding principle with which his administration will confront every challenge.

He is beginning his presidency just as the UK is about to start formal Brexit negotiations. In 2019 we could be outside the European Union.

Donald Trump treated the inauguration as his biggest rally yet, delivering the same brand of epic promises that defined his campaign

Mrs May’s Government is on an urgent mission to secure a raft of international trade deals. The prospect of the UK winning unfettered access to US markets could strengthen her hand in the EU negotiations.

Her own visit to the White House – the first of any world leader – was a signal that the UK Government has no intention of giving Trump the cold shoulder, no matter how much individual MPs might loathe the man.

The debacle also demonstrates that the Queen is the UK’s ‘soft-power’ super-weapon

There was the amazing filmed segment during the 2012 Olympics ceremony when the Queen was seen conversing with James Bond. The monarch is a cultural icon on a par with any fictional creation to emerge from these isles.

Governments are more than willing to use her as a tool of foreign policy.

The Queen is more effective than an aircraft carrier when it comes to projecting British influence abroad

As Conservative MP Crispin Blunt put it last week: “Dangling a state visit in front of a half-Scottish President of the United States, whose mother had an immense attachment to that country, was an exercise in pressing the right buttons to engage him and a successful use of the United Kingdom’s soft power.”

The days when the Royal Navy could dispatch the world’s most fearsome battleships to ports across the globe may be gone but the leaders of superpowers look enchanted and even awed when they shake hands with the Queen.

Why the fuss about Trump when despots regularly visit Britain?

There are plenty of people who have raised an eyebrow at the cries of protest that she will soon welcome Trump to these shores.

Yes, Trump has been recorded saying things about women, Muslims and Mexicans that would force the resignation of a UK minister, but state visits have been granted to the leaders of countries with odious human rights records – so is the fuss about Trump quite out of proportion?

After all, the Queen greeted Chinese President Xi Jinping in 2015, Egypt’s President Hosni Mubarak in 1991, Saudi Arabia’s King Fahd in 1987 and Nicolae Ceauşescu of Romania in 1978.

Nicolae Ceausescu, President of the Socialist Republic of Romania, and his wife Elena were introduced to Prince Charles by the Queen at Victoria Station during a state visit in June 1978

The key difference is that when a UK Prime Minister or monarch meets with someone from a country where torture is rife and the death penalty is regularly used and minorities are scapegoated and persecuted there is a hope – however faint – that they will be impressed by our values and tugged away from barbarism.

But the UK has not traditionally sought to steer the US from falling off a moral precipice. The “special relationship” has been energised by the idea that the UK and the US share one another’s values.

We're used to holding friends to higher standards

Trump has scandalised people in this country by talking up the effectiveness of torture; his comments about what he felt he could do to women generated disgust and horror; and his approach to different minority groups has proved equally troubling.

His visit will trigger protests by people who want to show the world that the people of the UK do not share such attitudes and that our hospitality is not an endorsement of his policies.

Yes, Trump is a master of using controversy for political gain. But all showmen want to be loved, and perhaps this visit will force him to ask why so many people are frightened rather than thrilled by his spectacular rise to power.