Trump's NATO pressure spurs European defence spending but fuels alliance doubts

U.S. pressure on NATO to raise defence budgets has prompted European allies to boost spending and seek alternatives to American weapons, even as a Pentagon review of U.S. forces in Europe creates uncertainty about the alliance’s long-term unity. At Romania’s Mihail Kogalniceanu Air Base, about half of the 2,000 U.S. troops stationed there last year left, but nine KC-135 refuelling aircraft remain, underscoring Washington’s continued reliance on European sites for operations in the Middle East.

Trump has repeatedly threatened to cut U.S. troop numbers and criticised allies for not meeting spending targets, prompting a six-month review that could examine up to 57 criteria, including each country’s public support for U.S. foreign-policy priorities. Defense Secretary Pete Hegseth warned that some allies might “fail” the review, and senior Pentagon officials said the process is “rigorous, consultative and empirical.”

Despite the rhetoric, the United States still invests in key NATO infrastructure, with new construction contracts at Spain’s Morón base and ongoing expansion at Romania’s air base. Yet at least eight NATO members – including Canada, Poland, Denmark, Spain, Norway, Turkey, France and Germany – are actively looking to reduce dependence on U.S. defence firms, purchasing non-American radar systems, jets and other equipment.

"The pressure on Europe worked, but it created real uncertainty," said J.C. Lintzenich, a former senior U.S. military intelligence official. > "Europe is spending more, taking defence more seriously, and accepting greater responsibility – that is a real success. But there is also genuine concern in Europe that the United States could abandon them."

White House spokesperson Olivia Wales asserted that Trump has done more for NATO than any predecessor, while NATO officials highlighted recent comments from Secretary-General Mark Rutte praising the president’s role in driving higher defence spending. Analysts, however, warn that the alliance’s core deterrent – Article 5 – is weakened by eroding transatlantic trust.

Russian incursions near Romania, Poland and Germany have heightened security concerns, prompting NATO to scramble fighters and intercept drones. European officials say the incidents test NATO’s response capabilities and underscore the importance of continued U.S. presence.

The review’s outcome could shape future force levels, with some officials suggesting a possible cut of up to 25,000 U.S. troops – a figure that would fall below the congressionally mandated 76,000-troop minimum. Until the review is completed, NATO members are preparing for a scenario in which Europe assumes greater defence responsibility while still relying on American strategic assets.

The shifting dynamics reflect a broader trend: NATO’s European members and Canada increased combined defence spending by about 20% in 2025, driven by both the war in Ukraine and U.S. pressure. Yet growing doubts about U.S. reliability are prompting many to diversify procurement, a move that could have long-term implications for the U.S. defence industry and the alliance’s cohesion.