NATO Secretary-General Mark Rutte offered EU policymakers a blunt assessment last week: Europe cannot defend itself without the United States. Anyone who thinks otherwise, he said, should “keep on dreaming.” His message comes amid an intensifying debate over how, and how far, Europe should shoulder its own security.
That debate has intensified since late last year, when U.S. officials signalled that the European Union has until 2027 to take on responsibility for much of NATO’s conventional defense.
Since then, U.S President Donald Trump’s threats over seizing Greenland, coupled with a national security strategy that frames Europe as a liability rather than a partner, have only sharpened the sense of urgency in European capitals.
Yet Rutte insists that the answer is not separation from NATO, but stricter adherence to its internal logic. He continues to argue for a “stronger than ever” EU–NATO partnership — provided the existing division of labour remains intact.
“NATO is good at standards, capability targets, command and control. The EU has its strength in the internal market, [...] resilience, regulation,” the Alliance's chief told the European Parliament on Monday. “So, my plea is, let's really focus on that division of labour so that collectively we can be as strong as possible.”
But Washington’s increasingly erratic posture has prompted calls across Europe to go beyond the established working arrangements and build a robust European pillar within NATO.
In practice, building such a European pillar would demand far more than higher defense budgets, forcing governments to confront hard choices about coordination, capability and political ownership that many have long deferred.
The price for replacing American power
European countries would need to invest around $1 trillion over the next 25 years to replace critical American conventional capabilities — from strategic aviation to space assets — according to the Washington-based International Institute for Strategic Studies (IISS). But analysts agree that money alone will not solve the problem.
“If our immediate task is simply to invest in building up our immediate capabilities for deterring Russia, we do have a lot of encouraging signals and we are to a certain extent on track,” Alexander Burilkov, assistant director for research at the Bratislava-based GLOBSEC think tank, told The Parliament.
The real challenge, Burilkov said, is developing high-end capabilities. Europe remains heavily dependent on U.S. equipment and services in areas such as long-range missile defense and satellite intelligence. The IISS estimates that while some gaps could be closed by the end of the decade, others would take at least another 10 years.
Europe’s defense industry insists progress is already underway. The EU has lifted defense efforts to levels not seen in decades, recently launching GOVSATCOM, a sovereign satellite communications system independent from the U.S. Other flagship projects, including the Eastern Flank Initiative, the so-called drone wall and the European Space Shield, are also advancing.
“The key challenge for Europe is not only staying on course, but accelerating prioritisation, coordination and readiness fast enough to deliver credible deterrence in the near term,” Estelle Hoorickx, senior captain and fellow at the Royal Higher Institute for Defence, told The Parliament.
Time for a European army?
Against the backdrop of Russia’s aggression and U.S. threats over Greenland, EU Defence Commissioner Andrius Kubilius has revived a long-dormant idea: the creation of a 100,000-strong European army.
“Would the United States be militarily stronger if they would have 50 armies on the state level instead of a single federal army?,” he asked at a Swedish security conference on Sunday. “If our answer is 'no, the US would not be stronger’, then what are we waiting for?”
To Rutte, however, such a move would add duplication and complexity rather than strength.
“It is vital that the EU’s efforts on defence are compatible with NATO”, Rutte told European lawmakers on Monday. “They complement what we already do, and what we already have.”
He also pointed out that a fully autonomous European defence posture would be far costlier than the 5% of GDP benchmark agreed by NATO allies in The Hague last year.
Going at it alone, he also warned, would mean forfeiting the U.S. nuclear umbrella.
Public opinion across the bloc, however, appears to be bending away from that of Rutte and other critics. Strong majorities of Europeans across all age groups now favor deeper defense integration, according to a 2025 Eurobarometer survey. Another poll from the German Council on Foreign Relations found that 69% of Germans support the creation of a common army.
The future of NATO’s top command
While the U.S. has long urged Europe to take responsibility for the continent’s conventional defense, there is far less agreement about whether this should extend to NATO’s top military command positions, including the role of Supreme Allied Commander Europe (SACEUR).
Last year, the U.S. ambassador to NATO suggested that Germany could assume leadership of the Alliance’s senior military posts — positions that have always been held by an American general or admiral.
“The ideal path for NATO is that Europeans take the major command posts at SACEUR level, but also at operational level, in Naples, or in Rammstein [two of the most critical strategic hubs], and the Americans stay at chief of staff level,” Michael Benhamou, founder of the Europe’s War Institute (OPEWI), told The Parliament.
Benhamou, a former NATO political adviser, argued the Alliance should adopt a rotation system among key European allies. Under such an arrangement, Germany, France, the UK, Italy and Poland would each hold NATO’s top military post for periods of 18 months to two years. Other European countries could rotate into leadership roles at operational and tactical levels.
“That idea also fits the budget realities, as the Americans give less and less to NATO in terms of common funding and troops in Europe,” Benhamou added.
Today, the U.S. maintains between 70,000 and 90,000 permanent troops in Europe and contributes nearly 15% of NATO’s annual budget — roughly the same share as Germany. In 1990, Washington had 213,000 soldiers stationed on the continent.
The road ahead for Europe’s security role
Mounting calls to operationalize the EU’s mutual defence clause, create a pan-European military force and establish a European Security Council — as proposed by Kubilius — suggest that the bloc has grown weary of its reliance on U.S. security.
But rhetorical momentum doesn’t necessarily translate to readiness.
Rather than outright control of the Alliance, European leadership is more likely to emerge through “flexible political formats and coalitions, such as the Weimar Triangle or the Bucharest Format, reflecting differing threat perceptions and strategic priorities among European allies,” Hoorickx said.
She added that if NATO were to weaken severely — or fracture altogether — a new European security architecture would also be more likely to emerge from ad hoc coalitions of willing states, including key non-EU allies, rather than through existing European defense structures alone.
“The most likely, and perhaps the best, scenario is not for Europe to lead NATO by 2027 in a comprehensive sense,” Hoorickx said. “But rather to assume greater responsibility within the Alliance.”
For Europe, the path forward is becoming clearer: taking on greater responsibility for its own defence may be the most credible way to sustain the Alliance, even if full strategic autonomy remains out of reach for now.
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