Further reductions could create vulnerabilities as pressure on the alliance intensifies
Two of the pillars underpinning NATO deterrence have come under significant strain since the beginning of 2026: the rapid depletion of US munitions stockpiles resulting from the war with Iran and the substantial limits placed on US contributions to NATO’s Force Model in the event of a future conflict.
Against this backdrop, the Pentagon has launched a review of the US military posture in Europe. The Secretary of War is expected to receive several options for the size and distribution of American forces on the continent in early November. The process is scheduled to conclude in early December, after which President Donald Trump will decide whether to accept, amend or reject the department’s recommendations, likely following consultations with the National Security Council and the State Department.
A periodic and clear-eyed review of America’s commitments in Europe is prudent. However, given the Kremlin’s increasingly active military and hybrid campaign against European states, and the fact that Europe’s rearmament has yet to reach the required pace, a serious strategic assessment should conclude that the United States must maintain a robust force posture in Europe.
Little room remains for further reductions
The United States currently has approximately 80,000 permanent and rotational troops deployed across Europe. That figure is already below the post-Cold War average of roughly 94,000 permanently stationed American troops.
The US military has only three fighter wings permanently deployed in Europe and no strategic bombers permanently based on the continent. Most of the US Navy is operating in the Pacific.
Only a command-and-control ship in Italy and five destroyers based in Spain are permanently stationed US surface vessels in Europe. Those destroyers have been repeatedly deployed to the eastern Mediterranean for operations in the Middle East, limiting their ability to participate in exercises with NATO allies. A sixth destroyer was expected to join US naval forces in the theater in October.
Under these conditions, further cuts would not simply eliminate excess capacity. They would directly affect essential missions and capabilities.
European bases remain critical to US operations
The war with Iran has further demonstrated the importance of access to European bases and airspace. The Pentagon could not have sustained the same intensity and duration of strikes against the Iranian regime without the basing, transit and overflight rights provided by European allies.
The US presence in Europe is also heavily subsidized indirectly by European taxpayers. American bases support not only NATO deterrence and US global power projection, but also Washington’s political influence across the continent.
The deployment of US forces in Europe also continues to enjoy substantial public support in the United States, including across different political constituencies.
Moscow is testing the alliance’s limits
The review is taking place at a sensitive moment. The Kremlin appears willing to test how far it can go before NATO fractures or acknowledges that a conflict with Russia is already underway.
A recent series of attacks and plots targeting European infrastructure — including an airport attack in Germany directly attributed to Moscow by Berlin, as well as an arson attack at a Polish drone factory that Prime Minister Donald Tusk described as very likely a Russian operation — points to a pattern of escalation.
The CIA director also reportedly recently visited Russia to deliver a warning against further adventurism targeting NATO members. At the same time, Moscow is closely tracking reports that US stocks of PAC-3 interceptors and ATACMS missiles in Europe have fallen to “beyond critical” levels.
Replacing these high-end capabilities could take years. The same time frame applies to compensating for reductions in the US contribution to NATO’s Force Model — the troops and capabilities expected to surge forward rapidly if a conflict were to break out.
European rearmament cannot immediately replace US forces
The substantial defense investments made by European states, encouraged in part by the Trump administration, represent an important and necessary development. However, those investments have not yet been fully converted into operational capabilities.
Allies are working to fill the gaps left by the United States, but they still lack sufficient capabilities — particularly high-end enablers — to replace American contributions withdrawn or limited earlier this year on a one-for-one basis.
Weapons production takes years, not months. That reality is evident in the Pentagon’s ongoing efforts to expand munitions manufacturing and replenish depleted stockpiles.
Signaling that the American cavalry available during a future European crisis would be limited places greater emphasis on the size and composition of the forces already based on the continent. Russia must remain convinced that the US presence, combined with the firepower European NATO members would bring to a conflict, is sufficient to deter direct confrontation.
Washington’s decisions will be closely watched
NATO deterrence, sustained by an alliance of 32 members, depends on countless decisions and signals issued by governments across the alliance. For President Vladimir Putin, however, the United States remains the decisive actor.
If Moscow were to conclude that Washington was unable or unwilling to intervene meaningfully in defense of its allies, Russia could be encouraged to risk a conventional attack against NATO before Europe’s military rebuilding efforts reach critical mass.
Senate Armed Services Committee Chairman Roger Wicker recently warned against hollowing out the US presence in Europe before Europe has adequately rebuilt its military strength. He stressed that converting defense spending into actual military capability would take time, and that the force posture review must account for the possibility that a weakened Russia could resort to opportunistic aggression in Europe.
Congress will also play an important role in determining the future configuration of US forces on the continent. The fiscal 2027 National Defense Authorization Act is expected to reinforce restrictions already introduced against withdrawing US forces in Europe below a floor of 76,000 troops, while imposing additional requirements for any substantial reduction of the American presence.
For now, the credibility of Europe’s rearmament still depends to a considerable extent on the US forces already deployed on the continent and on Washington’s decision to keep them there.
NATO members, their partners and Moscow will be watching the review closely. The stakes are clear: any miscalculation could affect not only the US military posture in Europe, but also the credibility of the alliance’s entire deterrence system.
