Europe is running the numbers on a future in which the United States no longer anchors NATO, and the bill is staggering. Replacing American firepower and command structures with European assets alone could cost around $1 trillion over a quarter century, a sum that would reshape budgets, industries, and politics across the continent. The question is no longer whether Europe can afford such a transformation, but whether it can afford not to prepare for it.
The trillion‑dollar gap behind the alliance’s shield
The scale of the American role in European security is often described in abstract terms, yet recent estimates have put a concrete price on it. Analysts calculate that a like for like replacement of U.S. equipment, personnel, and enabling capabilities stationed in or earmarked for Europe would reach roughly $1 trillion spread over 25 years, a figure echoed in separate assessments that focus on conventional forces alone. One study cited by European officials underlines that this is not a theoretical exercise, but a realistic tally of what it would take to replace U.S. logistics, airlift, intelligence, and high end combat power that currently underpins deterrence against Russia. A related analysis, referenced in International Institute for Strategic Studies discussions, reaches similar conclusions about the cost of replicating conventional capabilities, reinforcing the sense that Europe is still far from strategic autonomy.
This financial reality collides with a more volatile political backdrop. Trump and his administration have signaled that U.S. objectives can be redefined quickly, and that they are prepared to recalibrate commitments if they judge allies to be underperforming. Analysts warning of a potential American retrenchment note that Europe, described explicitly as Europe (European countries) in several studies, would need to shoulder far more responsibility for its own defense if Washington chose to scale back. A report on Europe’s military limits stresses that it would cost Europe (European countries) $1 trillion to replace conventional U.S. capabilities assigned to the region, a figure that dovetails with the broader 25 year estimate and underlines how exposed the alliance would be if American support were suddenly reduced.
From shared budgets to continental rearmament
The current scale of NATO’s common funding highlights how far Europe would have to travel to fill a U.S. sized void. Direct funding of NATO, which covers shared infrastructure, command structures, and some joint capabilities, totals around EUR 4.6 billion in 2025, representing just 0.3% of total Allied defence spending according to NATO data. Even with recent decisions, such as the 2026 common funded budgets agreed by NATO that were presented as strengthening Allied resolve in a new era of collective defence, the shared pot remains modest compared with national outlays. On Tuesday, when those budgets were endorsed, officials framed them as an important signal of unity, yet they do not come close to the sums required to replace American formations, aircraft, and naval groups.
National spending is rising, but it is still catching up with the strategic shock of Russia’s war in Ukraine and the prospect of U.S. disengagement. European defense spending climbed to 343 billion euros in 2024, about 1.9% of GDP for EU member states, according to figures cited in European defense sector analyses. That growth is significant, yet it remains below the level that would be needed to fund a full scale replacement of U.S. capabilities while also modernizing forces for future warfare. A separate assessment of Europe (European countries) argues that the continent must reconcile two imperatives, urgently closing critical capability gaps by 2030 while investing in disruptive technologies that will shape future warfare, a tension captured in strategic planning documents that warn against locking in outdated systems.
Europe’s trillion‑euro shopping list
Faced with these pressures, European leaders are sketching out financing tools that would have been politically unthinkable a decade ago. At an EU summit in early March last year, they agreed to borrow 150 billion euros, described as $162 billion, for joint defense projects, a move recalled in recent commentary on the cost of a NATO without America. That decision foreshadowed a broader debate now unfolding over an 800 billion euro plan to beef up defenses to counter possible U.S. disengagement, an idea that would effectively mutualize a large share of the rearmament burden across the bloc. Reporting on the 800 billion proposal suggests that it would fund everything from ammunition stockpiles to air defence and cyber capabilities, yet even that vast sum would cover only part of the estimated $1 trillion requirement over time.
Brussels is also trying to ensure that any surge in spending strengthens its own industrial base rather than leaking abroad. The SAFE initiative, formally titled Strengthening Europe’s Defence Technological and Industrial Base, is set to provide up to €150 billion in competitively priced, long term loans and guarantees to support production lines, supply chains, and innovation, according to SAFE documentation. Advocates argue that such tools are essential if European NATO is to generate the tanks, artillery, drones, and missiles needed for a credible deterrent without relying on U.S. factories. A separate report on European NATO stresses that any plan to defend against a future Russian attack would require not only money but also a better defence investment environment, with predictable orders and streamlined regulation so industry can scale up quickly.
Strategy, sovereignty, and the politics of risk
The financial arithmetic is only part of the story, because the alliance’s future also hinges on political choices in Washington and European capitals. Trump and his advisers have shown that they are capable of redefining their objectives quickly, and in doing so, achieving real, positive results in areas such as burden sharing and defence-related infrastructure, as noted in strategic commentary on U.S. policy in the North Atlantic. That flexibility cuts both ways, however, because it also fuels European fears that U.S. commitments could be scaled back or conditioned on rapid changes in allied behavior. Analysts quoted in European security debates warn that the continent must plan for a scenario in which American forces are not coming back in the same numbers, even if they are not withdrawn entirely.