Trump's America Cannot be Trusted. What Should We Do?

In September 1938, the Head of the British Foreign Office Alexander Cadogan realised that Britian’s policy of appeasement had failed. He wrote to five trusted colleagues to seek their advice on a new policy. One of these was Admiral Sinclair, the Chief of SIS (MI6), who responded promptly with a paper entitled ‘What Should We Do?’ based to a significant extent on the reporting of one secret agent who had befriended the top German leadership. That agent and his influence on UK foreign policy is the subject of my forthcoming book The Spy and the Devil.

Sinclair recommended in 1938 that Britain should continue to appease Germany until it had built up enough military strength to fight and win. His suggestion was to replace all the years of feckless appeasement with a much shorter period of deliberate tactical appeasement.

March 2025 feels very similar. Prime Minister Starmer deserves a great deal of credit for how he has acted over the past month. However, he will soon need to decide whether the relationship with the Trump administration is manageable or whether an entirely new approach is required.

Hitherto he has been acting as if President Trump’s policy towards Ukraine is somehow an aberration. If only Trump could be shown the real position he would come round to a more balanced policy. But it is not an aberration. Trump’s admiration for Putin can be documented for at least a decade. He even described the February 2022 invasion of Ukraine as ‘genius’ and ‘savvy’. His dislike of Zelensky stems from thwarted political motives. A re-reading of John Bolton’s book The Room Where it Happened reveals Trump’s primary motivations as personal animosity, overweening vanity and bizarre fixations.

Some commentators have tried to explain Trump’s approach to Ukraine as part of a masterly geopolitical strategy to focus more resources and effort against China. But it is by no means clear that Trump wants a new Cold War with China. Yes, he wishes to rebalance the trade relationship, but it is not even certain that he wishes to defend Taiwan. Indeed, he has shown similar admiration for Xi Jinping’s brand of dictatorship as he has for Putin’s.

Starmer played to Trump’s vanity by deploying the King’s invitation for a second State Visit. It was a big card to play so early in a dialogue, but he had little option. He could hardly have made it contingent on a security backstop in Ukraine. Earlier there had been some minor tactical appeasements. The UK might have put out a statement in support of Canada after Trump’s suggestion that it would become the 51st state (the EU was altogether more vocal in its support for Denmark over Greenland). But nothing was said about Canada for fear of derailing the (then crucial) Starmer visit to Washington.

Starmer’s motives have been completely understandable. It is too early to conclude that the UK’s relationship with the US is irreversibly damaged. There is far too much at stake. Any break in relations could endanger GCHQ’s unique intelligence-sharing arrangements with the NSA and threaten the future of the Five Eyes. Equally importantly, the medium-term effectiveness of Britain’s nuclear deterrent – which relies on US Trident missiles inside the UK’s huge (and vastly expensive) ballistic missile submarines – would be called into question. Several other defence partnerships would also be at risk; not least the F-35 programme. Yes, the UK could buy more Typhoons instead but they are a generation behind and only short takeoff and landing aircraft (currently F-35Bs) can fly from the country’s two aircraft carriers.

By contrast, one can debate the wisdom of some of the means of trying to save the US–UK relationship. Starmer’s seeming fixation on putting UK boots on the ground in Ukraine is injudicious. True, it is predicated on a US backstop assurance, but that is not an assurance on which the UK (or France or indeed any other European country) can rely anymore. Furthermore, UK troops are neither trained nor equipped to fight (in extremis) hardened Russian units in Ukraine. Rules of Engagement would need to be crystal clear and agreed between all allies. Either military defeat or, more likely, a humiliating decision to allow Russian invaders to bypass the peacekeepers (as in the Balkans and Lebanon) could be the result.

Fortunately Putin will never permit NATO peacekeepers in Ukraine and (if his Afghan negotiating prowess is anything to go by) Trump will concede the point to the Russian leader. The best troops to police any agreed Ceasefire Line will be Ukrainians who will need to be furnished with the best equipment which Europe can provide. In the absence of a US backstop Britain and France will have to supply it; presumably in the form of aircraft operating out of Poland, Romania and the Baltic States. But when push comes to shove, would Britain or France really go to war with a Russia which might have crept, say, five miles over the Ceasefire Line with some faux-credible pretext intended to test allied resolve?

A second area where Starmer and Europe may have been guilty of appeasement is over minerals. From the outset Trump’s minerals deal smacked of blackmail. Indeed, Zelensky’s wish to leverage the deal in return for a backstop provoked the (probably confected) confrontation in the White House. Zelensky has clearly come under pressure from the Europeans to sign it even in the absence of any backstop guarantees. Trump’s claim that the presence of US mining engineers in Ukraine would be as good as a backstop is patently false. Just because there are some US workers at a Titanium or Lithium mine in Ukraine (or even at 15 or 25 such mines) would not prevent another Russian invasion. Moscow would just need to be careful not to kill any (or too many) Americans.

Even after Zelensky’s diplomatic surrender on 4 March the Trump administration slapped an intelligence sharing ban on Ukraine. Perhaps this further proof of bad faith can help the UK foreign policy establishment to decide whether the new Trump administration is just a more extreme version of traditional American isolationism or a personal populist cult (with distinct overtones of ‘State Capture’) which has sucked in the whole Republican party (some driven by ambition and enthusiasm and others by fear). To paraphrase Margaret Thatcher on Gorbachev: Is this a man we can do business with?

In so deciding Starmer may need to consider that there could be 12 years of this type of maverick (or new-normal) government; four years of Trump followed by eight years of the more extreme Vance. Furthermore, will Europe hold together? The arrival of Friedrich Merz could shore up a core group of Germany, France and the UK. Italy would be an ideal fourth member, but Georgia Meloni might well defect to the Trump camp along with Hungary, Slovakia and Austria. Fortunately, there should be two clear years to make progress before (in a worst case) the AfD make further gains in Germany, and Le Pen wins the French presidential election in 2027.

At the root of this shambles lies the failure of traditional liberal democracy to deliver change and prosperity for its people. This is fertile ground for authoritarian populism. Sinclair’s advice in 1938 was wise but in late 1938 Spitfires and Hurricanes were rolling off the production lines in increasing numbers, whereas, in 2025, European defences are in a parlous condition.

Perhaps the tactical appeasement of Trump is working. The ceasefire proposal which emerged from the Jedda meeting indicated a better American balance between the two sides. For the first time Russia is feeling some diplomatic pressure. But it could be argued that Europe’s tough stance on economic relations and its early signs of military independence have been equally effective in influencing the US president.

‘What should we do?’ Europe (and Canada) needs to keep up the pressure on Trump and the US economy by reciprocating any tariffs and by demonstrating the massive downside to the US of alienating its allies. Meanwhile in London and Brussels the main planning priority should be devoted to devising a credible European backstop to guarantee any peace deal in Ukraine while also deciding what Europe would do if Russia were to refuse a deal and start to make significant military progress westwards across Ukraine. Keeping the US engaged will be important but Trump and the US can no longer be trusted with Europe’s security.

Sinclair wrote in 1938: ‘we should unremittingly build up our armaments and defensive measures and maintain them at the highest possible level, never relaxing. If we emerge from this crisis without war, we should take this lesson to heart.’

© RUSI, 2025.

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