Can Europe Defend Itself Without the U.S.?The Cost of Building an Independent Military and Nuclear Deterrent

Within hours of his party’s electoral victory, Friedrich Merz, Germany’s likely next chancellor, made a striking statement on national television. He warned that Donald Trump “does not care much about the fate of Europe” and stressed the need for Europe to achieve “step-by-step independence from the USA.” This was not a distant ambition. Merz expressed doubt about whether NATO would still exist “in its current form” by June, when leaders are set to meet in the Netherlands, or if Europe would need to “establish an independent defense capability much more quickly.”

For those who considered Merz’s warning alarmist, subsequent events provided a stark reality check. On February 24th, the United States aligned with Russia and North Korea in voting against a UN resolution proposed by its European allies that condemned Russia’s invasion of Ukraine. Shortly after, the U.S. introduced its own resolution in the Security Council, backed by Russia and China, calling for a “swift end” to the war—without reaffirming Ukraine’s territorial integrity.

Even NATO stalwarts are now grappling with the reality of an uncertain American commitment. Anders Fogh Rasmussen, a former NATO secretary-general, argued in The Economist that “the security architecture that Europe has relied on for generations is gone and is not coming back.” He added that Europe must accept its “existential vulnerability” and the likelihood of standing alone.

The Challenge of European Self-Reliance

Realistically, it could take a decade before Europe could defend itself without American support. A key test case is Ukraine. European nations are discussing a potential military deployment to oversee a future peace agreement. France and Britain are leading talks about deploying a force—likely in the low tens of thousands—to Ukrainian cities, ports, and nuclear power plants rather than frontline combat zones.

However, such a mission would expose Europe’s military weaknesses. First, European forces are already stretched thin. Ukraine currently hosts around 230 Russian and Ukrainian brigades, though many are understrength. Most European countries would struggle to field even one fully equipped brigade. Second, a European deployment to Ukraine would leave significant gaps in NATO’s own defense plans. For example, Britain’s contribution would likely come from its high-readiness and reserve forces, weakening NATO’s broader war capabilities. Most critically, any European force in Ukraine would still require significant American support, particularly for intelligence, air defense, and logistical backup in the event of a Russian attack.

Europe’s struggle to assemble even a division-sized independent force for Ukraine highlights the daunting scale of Merz’s vision. Meeting NATO’s current war plans—even with U.S. involvement—would require European nations to raise defense spending to 3% of GDP, a significant increase from present levels. The UK has pledged to reach 2.5% by 2027, but even that may be insufficient. NATO’s secretary-general, Mark Rutte, is pushing for a 3.7% target, and some analysts suggest that fully replacing American capabilities would require spending well above 4% of GDP.

The Practical Difficulties of European Military Expansion

Funding such an effort would be challenging, but converting financial investment into real military capability is even harder. Bruegel, a Brussels-based think tank, estimates that Europe would need to form 50 new brigades—many equipped with heavy armor—to replace the 300,000 U.S. troops expected to deploy to Europe in the event of war. Recruiting sufficient personnel for such an expansion would be difficult, as European militaries already struggle to meet existing staffing requirements.

Furthermore, military strength is not just about raw numbers. For example, Bruegel estimates that Europe would need 1,400 tanks to prevent a Russian breakthrough in the Baltic states, but that figure is based on traditional planning assumptions and may be excessive. More important than tank numbers is Europe’s ability to conduct high-intensity warfare. Europe possesses advanced air forces, but they lack adequate stocks of precision munitions, as noted by Justin Bronk of the Royal United Services Institute (RUSI). Additionally, pilot training across much of Europe is insufficient for the demands of modern warfare. While Sweden maintains high pilot proficiency, other European air forces lag behind. Crucial capabilities like airborne electronic warfare and intelligence, surveillance, and reconnaissance (ISTAR) are almost exclusively provided by the U.S.

Command and Control: A Glaring Weakness

Another major hurdle is European command and control. NATO’s Supreme Headquarters Allied Powers Europe (SHAPE) in Mons, Belgium, is led by an American general, as has been the case for every Supreme Allied Commander Europe (SACEUR). “NATO coordination is often a euphemism for U.S. staff officers,” notes Matthew Savill of RUSI.

Currently, expertise in commanding large-scale formations is mostly concentrated among British and French officers, though Turkey and Poland are improving as their militaries expand. However, even Britain would struggle to manage a large-scale air operation comparable to Israel’s air war in Gaza and Lebanon. “We’re still absorbing the lessons of modern AI-assisted data-basing and targeting,” says Savill. Europe lacks anything approaching Israel’s reported capabilities in this area.

Industrial and Logistical Dependence on the U.S.

Even if Europe builds a capable military force, the question remains whether it could sustain operations with sufficient munitions and equipment. European artillery production has surged since 2022, yet Russia—bolstered by North Korean support—remains ahead. While European nations have ramped up procurement, 34% of new NATO equipment purchases since February 2022 still come from the U.S., according to the International Institute for Strategic Studies (IISS). American supplies remain critical for key capabilities, including long-range rocket artillery, stealth aircraft, and advanced air defense systems. Shortages have forced European countries to buy armaments from Brazil, Israel, and South Korea.

Dependence on the U.S. varies by country. Britain is particularly intertwined with American military and intelligence networks. A sudden cutoff of U.S. satellite imagery and geospatial data, for example, would be highly disruptive. Even Britain’s Storm Shadow cruise missiles require American targeting data. However, interdependence works both ways: 15% of components in the F-35 fighter jet, including the ejector seat, are British-made.

The Nuclear Question

The greatest challenge in Europe’s pursuit of independence is nuclear deterrence. For 80 years, European security has relied on America’s nuclear umbrella. If the U.S. withdraws, it is not only troops that would be absent, but also strategic and tactical nuclear weapons.

On February 21st, Merz raised the issue publicly, suggesting discussions with Britain and France—Europe’s two nuclear powers—about expanding nuclear-sharing arrangements. However, Anglo-French nuclear forces cannot replicate U.S. capabilities. France and Britain have about 400 nuclear warheads combined, compared to Russia’s 1,700 deployed warheads. Expanding these arsenals would take years and divert resources from conventional forces. In Britain, nuclear forces already consume a fifth of the defense budget.

Ultimately, nuclear deterrence is as much about political resolve as it is about numbers. Some argue that Putin may take threats from London or Paris more seriously than from Washington. These debates, once central during the Cold War, have returned as Europe faces an increasingly precarious future. As Merz starkly put it on February 24th, “This is really five minutes to midnight for Europe.”