How Should Starmer Deal with Trump?

In 2022, Russia shattered the post-war European security order with its full-scale invasion of Ukraine. The shock of Putin’s aggression and brutality immediately reinvigorated a Euro-Atlantic alliance that had just failed in its most ambitious operation in Afghanistan and had been accused by French President Emmanuel Macron of experiencing ‘brain death’. Russia became an international pariah, NATO gained two new members, and Ukraine became central rather than peripheral to European security. However, in just one month since his reinauguration, President Trump has exhausted this transatlantic unity, together with the hope that Ukraine might prevail and Russia decisively ‘lose’. The developing crisis is far worse than the situation in 2022, as the source of instability is the Commander-in-Chief of NATO’s preeminent power, rather than its traditional enemy.

Trump – unlike most European leaders – has a strong mandate, a convincing ideology, and a plan. He is also executing his foreign policy agenda at a speed which the sluggish bureaucracies of Europe cannot cope with. While the language coming from the US is cruder and more direct, no politician or policymaker on the continent should be genuinely surprised. Trump has long signalled his desire to end the war in Ukraine quickly. The uncomfortable truth for Europe is that there is continuity between what Vice President JD Vance said at the Munich Security Conference and Defense Secretary Pete Hegseth’s speech to the Ukraine Defence Contact group, and what then Defense Secretary Robert Gates said on the future of NATO in 2011, when he warned that the US Congress and US taxpayers would lose their ‘appetite and patience’ for defending allies that are unwilling to defend themselves. The Europeans have taken the US for granted and must deal with the consequences.

Don’t Panic

The UK prime minister and his European counterparts must not panic. However, they need to truly understand the gravity of the situation and that the world – and their most important ally – is changing fast.

The UK and Europe have been so preoccupied with ensuring Ukrainian agency in any negotiations that they were completely blindsided by the initial freezing out of Europeans from US-Russian bilateral talks in Riyadh last week. These were only preliminary talks, but the US has already bent the knee to Russia and given Sergei Lavrov – the Russian foreign minister – the unrestrained glee of declaring the Europeans inconsequential.

Weekly therapy sessions at the Elysée Palace will not help. They risk European fatalism and weakness becoming a self-fulfilling prophecy. Last year, the EU’s combined GDP of approximately $17 trillion far exceeded Russia’s $1.7 trillion. However, while the EU also spends more on defence and has more active military personnel, when adjusted for purchasing power parity, Russia is now spending more on defence than European countries combined. If Trump readmits Russia to the G8 and lifts sanctions, its growing economy will speed up Russian rearmament and directly threaten NATO.

Therefore, Europeans must engage with Trump and his administration incessantly and break their preference to be insular and discuss among themselves as the world passes them by. This week, Starmer and Macron will be in Washington, and they must both speak in concert. As a preparatory step, Starmer should shelve his Chagos Islands deal – it is peripheral to the UK’s current security challenges and the money could be better spent on defence. Moreover, he needs support from his ministers at home to avoid distractions. His Chief of Staff should immediately reach out to the other parties and call for a domestic ceasefire to create political space for the prime minister and Cabinet to focus on Trump diplomacy. This is in the UK interest.

Recognising the Problems

This diplomatic offensive has many risks, and to be successful, Starmer needs to recognise the challenges he faces.

First, much more than the sovereignty of Ukraine is at stake. Putin not only wants to subjugate Ukraine; he also craves a much broader deal on European security which neuters NATO and recognises a Russian sphere of influence. His December 2021 ‘Draft Treaty’ issued to the US represented such ambitions, as did Medvedev’s 2009 draft ‘European Security Treaty’. Russia wants the future of Europe, NATO and Ukraine all on the table, with no ‘irritant’ Europeans present.

Second, there are no good options for Europe. European individual and collective defence and security deficiencies have robbed the continent of geopolitical power in a hardening world. The impotence of European powers on the world stage means they can be too easily shut out of conversations between the US, Russia and China. Therefore, the mission is not to develop perfect policies to enable Europeans to get to a decisively advantageous position. Rather, the priority – at least in the very volatile short term – is to mitigate the immediate risks to Europe.

Third, Trump will not be persuaded by facts. Starmer’s lawyerly background has been criticised for ‘dulling his political instincts’. Therefore, the prime minister must also appeal to Trump’s ego and emotions and make a strong case for what will happen to his reputation and standing if he gets played by Russia during negotiations.

Finally, despite the immediacy of the crisis, this is a long-term challenge. JD Vance is the presumptive Republican nominee in 2028 and perhaps even in 2032. Trump and Trumpism have successfully hijacked the modern US Republican Party, which has changed to the detriment of Europe’s interests and increasingly, its values.

Saving NATO

If the UK wants a ‘NATO first’ defence strategy, then its priority should be keeping the Alliance together in as close to its current form as possible. While Starmer has already broken ranks with Trump on the question of NATO membership for Ukraine, it is not the most pressing concern. If NATO falters, and allies and adversaries alike do not believe the US is committed to Article V, then Ukrainian membership will not provide the protections necessary anyway. Instead, Europe needs a greater understanding of the consequences of Hegseth’s remarks about what the US deprioritisation of Europe looks like in practice. Starmer should directly ask. Will NATO’s Supreme Allied Commander still be an American? Will the US disengage from NATO’s Nuclear Planning Group? Will NATO’s transatlantic reinforcement plan change? The answers to these questions will have a direct bearing on the UK’s ongoing Strategic Defence Review, alongside European defence postures and capabilities.

Starmer should also not be afraid to directly challenge the prevailing view of NATO in Trump world. He should emphasise the economic benefits of the Alliance, under Article 2 of the Washington Treaty, and its ability to support the US against the ‘pacing challenge’ of China. Moreover, he should remind the US of the role that allies played after 9/11 – a direct attack on Trump’s home city. It was a British Secretary General of NATO, Lord Robertson, who pushed for the invocation of Article V – the first and only time in the Alliance’s history. 457 British soldiers died in the subsequent conflict in Afghanistan, alongside 158 Canadians and 43 Danish troops. It should be a sobering reminder that those Trump castigates the most supported the US the most.

Securing Ukraine

The relationship between Trump and Ukrainian President Volodymyr Zelensky is deteriorating by the day, and could become far more volatile. At this point, a ‘peace deal’ seems elusive, but the UK and allies must be prepared not only for one to be forced on Ukraine, but for its implementation to be forced on Europeans. Thus far, Trump has signalled that the US will not put ‘boots on the ground’, but was favourable to Starmer being ‘ready and willing’ to deploy UK troops to Ukraine. However, the prime minister must not get ahead of himself, and should impress upon Trump that Europeans cannot – and will not – plan or agree any mission without some control over the settlement. Reportedly, a UK-French plan is for a ‘reassurance force’ of 30,000 European troops, backed by US enablers, strike capabilities and follow-on forces. This similar to the number that EU states (including the UK) had in Afghanistan at the height of the International Security Assistance Force mission, which stretched European forces. While Starmer is right to show willingness and prepare the electorate and Parliament for what might come, it is a huge risk. A minimum commitment of a brigade (5,000) sustained on rotation would require 15,000 in total to be allocated to the mission, with one brigade deployed, one training to deploy and the other on recovery. This would indefinitely absorb 20% of the total British Army strength and around 50% of the Field Army. However, the UK operated under US command at the Divisional level in Iraq and the Brigade level in Afghanistan, and would be a trusted partner to command and lead such a mission. This aspect is Starmer’s strongest negotiating tool for securing a ‘US backstop’, and he must make it clear that this is the only way it could work. If Trump is not forthcoming on US support, then the prime minister must refuse to send troops to Ukraine. For Europe, the worst possible outcome would be a failed reassurance mission. Best not to undertake the mission at all, rather than attempt a flawed one. Afghanistan, Iraq, Libya and the Sahel all demonstrate that European militaries have more experience of failure than  success.

The Arctic

The best way to keep the US engaged in European security is via the ‘backdoor’ of the Arctic. Hegseth’s recent comments were refreshingly direct:

‘We're also here today to directly and unambiguously express that stark strategic realities prevent the United States of America from being primarily focused on the security of Europe…We also face a peer competitor in the Communist Chinese.’

However, the 2024 US Department of Defense Arctic strategy identified the region as a ‘venue for strategic competition’ where China and Russia are cooperating the most. Therefore, another strategic reality for the US is that despite the desire to disengage from Europe, it cannot disengage from the Arctic. Trump’s designs on Greenland demonstrate the strategic importance of the Arctic to US interests.

In the Arctic, US and European interests most align. It is the playground for Russia’s strategic nuclear forces and prestigious northern fleet. A procession of vessels coming from the Indo-Pacific via the Northern Sea Route to  damage undersea infrastructure in the Baltic Sea, such as the New New Polar Bear in October 2023 and the Yi Peng 3 in November 2024, demonstrate China’s intent and its cooperation with Russia.

The UK, as the Arctic’s ‘nearest neighbour’ with the ambition to ‘lead and galvanise’ in the North - through NATO, the Joint Expeditionary Force (JEF) and the Northern Group – can offer the US support in the Arctic to keep its forces engaged in Europe. The JEF is well placed to keep the US engaged and stand up to Trump and US Republicans who think Europeans do not take defence seriously or support Ukraine enough.

In 2024, all JEF members met the 2% GDP NATO requirement and the 20% guideline on new equipment spend. Since 2014, the JEF collectively has averaged a real-terms increase in defence spending of 150%, compared to 108% for the rest of European NATO. Finally, as of October 2024, the 10 JEF countries had committed over $10 billion more in aid to Kyiv than the rest of European NATO members combined (including the larger economies of Germany, France, Spain and Italy), or 1.53% of GDP compared to 0.29% for the latter.

Therefore, the UK should not be worried about ‘breaking ranks’ with traditional allies such as France and Germany, and should leverage its significant minilateral relationships to work together to keep the US engaged as much as possible and to the benefit of Europe.

A Privileged and Costly Relationship

Ultimately, if the prime minister wants to act as a bridge between the US and Europe, reset relations with the latter, and commit to securing Ukraine, then he will have to pay for it. It will not be cheap, but the alternative would be far more costly. Therefore, at a minimum, Starmer should announce the long-delayed uplift in defence spending to 2.5% of GDP when he meets Trump. However, this is unlikely to be enough and could derail his plans before he can persuade Trump. If he really wants the UK to be at the top table, and for Russia – and China – to take the UK more seriously, he will need to commit to 3%, not ‘as soon as fiscal conditions allow’ but immediately.

© RUSI, 2025

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