It is a perennial fascination to witness the arrival of a new British Prime Minister on the global stage, and few figures have stepped into Number 10 with the chameleon-like dexterity of Keir Starmer. His blend of progressive aspirations and cautious pragmatism raises the question: will the Labour leader—now Prime Minister—herald a bold new era for UK foreign policy, or simply maintain the creaking but persistent “special relationship” with the United States? Nowhere is this question more acute than in defense policy, where the stakes are set to rise dramatically depending on the outcome of the looming 2024 U.S. election. Will Starmer steady Britain’s line, or will Labour’s ghosts lead him to take a path that Washington finds inconvenient?
NATO, defense spending, and global military collaboration hang in the balance. Starmer’s response to these challenges will not only define his foreign policy, but will also determine Britain’s place as a military power. It is a fine balance, and the winds blowing from Washington—whether from Kamala Harris in the White House or a potential resurgence of Trumpism—may well tip Starmer in one direction or another.
Let us begin with the man in question. Starmer is not one to be easily pinned down—too utilitarian to be a true ideologue, too ambitious to be cornered by the radical left. As a former Director of Public Prosecutions, he carries the aura of cold competence rather than the fiery zeal of his predecessor Jeremy Corbyn, whose flirtations with pacifism and disdain for NATO gave seasoned foreign policy hands in Washington palpitations. Starmer, by contrast, has been careful to distance himself from Corbyn’s anti-military posture, and his record in supporting British military aid to Ukraine signals that he is, at the very least, willing to play the part of a NATO loyalist. But can Starmer’s pragmatism withstand the centrifugal forces of Labour’s leftist wings, and the economic pressures his government is bound to face?
At the kernel of the UK’s defense debate lies a familiar but awkward question: military spending. Britain has long taken pride in meeting NATO’s benchmark of allocating 2% of its GDP to defence, and yet this figure is as much a symbol of relevance as it is a measure of military might. Under Starmer, however, the strain between domestic spending priorities and military commitments weighs heavily. Labour has promised ambitious investments in health, education, and a green economy—noble causes, to be sure, but ones that do not come cheap. In an era where public spending is a zero-sum game, Starmer will face intense pressure to trim defense budgets to fund his domestic agenda. This is where the 2024 U.S. election takes center stage. Should Kamala Harris emerge victorious, the U.S. will likely uphold its support for NATO, with a clear expectation that allies such as the UK will continue to carry their fair share of the burden. In this scenario, Starmer will have little choice but to sustain—if not increase—defense spending, especially as NATO confronts further tensions with Russia and China.
Yet, the prospect of a Republican victory in the White House and/or Congress, changes the calculus entirely. Trump’s tenure was marked by palpable disdain for NATO, previously calling it “obsolete” and badgering European allies to cough up more cash for their own defense. A return of such ethos would leave Starmer in a quandary. In the event the U.S. begins to withdraw its support for NATO, or pressures Europe to shoulder a larger burden, Starmer could well find himself tempted to slash defense budgets and prioritize domestic priorities, following Washington’s lead. Such a move would be hazardous—both for the UK’s standing in European defense, and for its ability to respond to global security challenges. But it would also be politically expedient for a Labour leader caught among a restless left and fiscal reality.
NATO has been the anchor of UK-US defense cooperation since its founding. Britain has long been instrumental in the alliance’s strategic planning and military interventions. Starmer’s pro-NATO stance during the Ukraine crisis, with his full-throated support for military aid to Kyiv, has reassured many that Labour, under his leadership, will not abandon its commitments. In the face of Russian revanchism and Chinese expansionism, NATO remains indispensable to UK security, and Starmer’s government knows that Britain’s military relevance hinges on its role within the alliance.
However, another Trump presidency could wreak havoc on NATO’s unity. Trump’s previous demands for European nations to “pay their fair share” were more than grandstanding—they were a harbinger of the U.S.’ waning patience with subsidising European defence. Should such sentiments return, Starmer’s government could face an uncomfortable dilemma. Would the UK be willing, or even able, to increase contributions to NATO to compensate for a shrinking American role? And if not, could Starmer pivot toward an alternative strategy—one favoring European defense mechanisms, perhaps even aligning more closely with the EU’s nascent defense initiatives?
Such a move would mark a profound shift in UK defense strategy, one that could sour relations with America. It is here that Starmer’s pragmatism will be tested. Would he prioritize keeping the UK to U.S-led defense strategies, or would he, like French President Emmanuel Macron, begin to chart a course toward greater European “strategic autonomy”?
Beyond NATO, the UK’s defence cooperation with the U.S. extends far and wide. The two countries have worked together on military operations from the deserts of the Middle East to the waters of the Indo-Pacific. Under Starmer, this global military partnership is likely to continue, though its scope may evolve contingent on how the U.S. chooses to wield its power post-2024.
The Biden administration has increasingly pivoted its focus to the Indo-Pacific, seeking to counter China’s growing influence. Initiatives like the Quad (involving the U.S., Japan, India, and Australia) and AUKUS (a defence pact between the U.S., UK, and Australia) are key pillars of this strategy. Britain’s involvement in AUKUS denotes a willingness to counter China’s ambitions, and Starmer, notwithstanding a marginal left-leaning base, has given zero indication that he would pull back from this commitment.
Yet, should Trump take emerge victorious, and pursue a more isolationist approach, the UK may find itself reassessing its military partnerships. If the U.S. scales back global commitments, particularly in the Indo-Pacific, Britain could be left in a precarious position—caught between its far-flung military interests or refocusing on European security, especially as tensions with Russia remain unresolved.
Keir Starmer’s premiership, much like his political persona, will be moulded by realism and compromise. The UK’s defence cooperation with Washington remains vital, but the future of this relationship depends on forces beyond Starmer’s control—namely, the 2024 U.S. election outcome.
Should Harris win, Starmer’s path is clear: continuity, strengthen NATO, and ensure Britain’s global military partnerships remain intact. But if Trump seizes the White House, the UK could face a more uncertain future. Starmer’s balancing act will then become more precarious, with the potential for rifts in the “special relationship” that has long defined UK foreign policy.
[Photo (cropped) by Simon Dawson – No 10 Downing Street, via Wikimedia Commons]
Mitchell Gallagher is a PhD candidate at Wayne State University, specializing in Sino-U.S. relations, Taiwanese statehood, and soft power. The views and opinions expressed in this article are those of the author.
