The PM’s visit could be seen as a diplomatic coup, but her vision of a free-trading Britain could crash into ‘America First’

Theresa May travels to the US on Thursday to try to forge a personal and political relationship with the least predictable and, in European terms, most unpopular US president in modern times.

For all the British diplomatic pleasure that their prime minister is once again the first foreign leader through the door of a newly elected president, as John Major managed in the case of Bill Clinton in 1993, there will be wariness in Downing Street. For the first time since the second world war, the US appears to have a president who displays indifference to supporting his allies or shoring up an alliance framework.

No 10 will seek to focus on the prospect of a mutually beneficial post-Brexit US-UK free trade deal, but even this will only serve to highlight the glaring inconsistency between Donald Trump’s broader ‘America first’ protectionism and May’s vision of a free trading global Britain.

Not surprisingly, there are no plans as yet for a joint press conference. Trump’s public performances have so far the quality of an unguided missile, veering off into unexpected directions, not dissimilar to the British independent nuclear deterrent.

There is also the contrast in personal style. A serious-minded and circumspect daughter of a clergyman, she has, unlike Nigel Farage, nothing culturally in common with Donald Trump. Pictures of her arm in arm with the president in the Rose Garden or sharing a thumbs-up sign will not be published. May is not needy in that way. Equally there is little chance she will be sending private hand-written notes in the manner of Margaret Thatcher to Ronald Reagan: “Anything that weakens you, weakens America; and anything that weakens America weakens the free world.” Trump and May share an interest in the populist forces that drive Brexit, but they are not ideological soulmates, exchanging first editions of Hayek.

Facebook Twitter Pinterest Margaret Thatcher and Ronald Reagan at the G7 Summit in Toronto, 1988. Photograph: Gary Hershorn/Reuters

Still more, the May campaign team can see from the fate of one of her predecessors, Tony Blair, that excessive proximity to a disliked US president can disable your own premiership. George W Bush was not only unpopular in the UK due to the decision to go to war in Iraq in 2003, but also his views on climate change and general unwillingness to communicate in a way that might resonate with European audiences. “Yo, Blair” was the least of it.

Blair repeatedly, including in his own autobiography, tried to challenge the settled British view that Bush was unintelligent, writing: “One of the most ludicrous caricatures of George is that he was a dumb idiot who stumbled into the presidency. No one stumbles into that presidency.” Ironically it was Margaret Thatcher who privately confided her great friend Reagan was ignorant.

But every time Blair eloquently defended Bush’s unilateralism, the charge of poodle-ism stuck more. Even among Democrats such as Jimmy Carter’s national security adviser Zbigniew Brzezinski, the special relationship under Blair was perceived to have become an unbalanced one.

Facebook Twitter Pinterest Tony Blair and George W Bush in the White House after speaking to reporters about Iraq, May 2006. Photograph: Kevin Lamarque/Reuters

Polling dating from last summer by the Pew Research Center show the risks of going much beyond a transactional relationship. The polls found Trump deeply unpopular in Europe; only 12% of British people said they had confidence that President Trump would do the right thing regarding world affairs. An extraordinary 85% of British people had no confidence. By contrast 60% had confidence in her defeated rival Hillary Clinton. Indeed, British voters had only marginally more confidence in him than Vladimir Putin.

There is little to suggest as she enters the Oval Office that there has been a sea-change in British opinion since last summer.

Indeed, many British people believe she will be going into the office of a deranged, sexist narcissist, willing to let his military loose to torture its enemies.

May has already firmly suggested that on issues such as sexism and free trade she will state her views and differences frankly. But it is a difficult balancing act. Trump is notoriously thin-skinned, and she cannot afford to offend her host. That is the meat and drink of diplomacy.

The pressure for her is that she cannot afford to see the relationship weaken. After burning its bridges with the European Union, the UK simply cannot let the American alliance loosen.

More broadly on policy, May’s team will have to judge the limits of its influence, and on a first meeting will be looking for areas of commonality such as security, trade deals and the fight against Islamic State.

In a bid to get closer to the Trump world view, the foreign secretary Boris Johnson has already executed a manoeuvre on the Middle East. Before Christmas the UK backed a UN resolution condemning illegal settlements by Israel.

But in the past fortnight the UK, alone in Europe, has ostentatiously condemned a French Middle East peace conference communiqué, blocked an EU foreign ministers motion supporting the conference and a further similar statement at the UN.

The UK insists it remains committed to a two-state solution, but it has at the least distinguished itself from its French partners in a way that Trump and his son-in-law Jared Kushner will notice.

Facebook Twitter Pinterest President Donald Trump signs executive orders on 24 January, watched by Jared Kushner (right). Photograph: Rex/Shutterstock

It will be interesting to see if similar shifts are in the offing over Syria through less emphasis on President Bashar al-Assad standing down as a precondition for talks, a position the Turks under Russian influence may be willing to adopt. Equally, in Libya, the UK has so far backed the fragile UN endorsed Government of National Accord, but Russia supports the authoritarian General Haftar. Could Trump swap horses in Libya and back the strong man? The outgoing US Libya special envoy Jonathan Winer in an address on Wednesday advised not, saying an attempted military conquest by Haftar would be suicidal and only strengthen extremism.

May will also probe Trump on Russia sanctions and Iran, two issues on which the UK have been the most forward in Europe. The Trump administration, notably the State Department, now seem less keen to tear up the Iran nuclear deal, something that will please the UK. On Russia, the UK knows that if Trump is intent on testing out a new personal relationship with Putin, the great deal-maker cannot be stopped.

The Foreign Office is still scarred by the Iraq experience, an episode that laid bare the limits of UK influence over Washington. In the conduct of that war Britain was only in the most theoretical terms a co-equal. Jeremy Greenstock, the then UK ambassador to the UN, in his book describes how “Britain was always sitting in the second carriage, and not in the engine room.”

Only a limited number of requests for changes of policy could be loaded into any one conversation between a prime minister and a president. In this first conversation there will be few British requests, but many questions.