“This will be a real review,” Elbridge Colby, the U.S. Undersecretary for Defense, wrote on X as the Pentagon opened its look at American forces in Europe. His stated aim: that NATO is “moving fast and irreversibly toward Europe taking primary responsibility for its conventional defense.”
The review began on a Tuesday and will decide how many troops and military assets the United States keeps on the continent. Defense Secretary Pete Hegseth announced it in June at a NATO ministerial meeting. It is set to run about six months, in consultation with allies and Congress.
NATO 3.0
Colby calls his vision “NATO 3.0.” Europe would supply most of the conventional military capability, while the United States serves as the main nuclear guarantor and strategic backstop. A CSIS analysis puts the central question plainly: can Europe build enough capability to deter Russian aggression, and defeat it if necessary, as the U.S. conventional share shrinks?
Cuts have already started, CSIS notes, since President Donald Trump returned to office. The United States is removing 5,000 troops from Germany and 700 personnel from Romania. In Estonia the American presence is falling from roughly 500 to 700 troops to fewer than 100, pending decisions tied to the review. The Pentagon also cancelled an armored brigade rotation to Poland. That could take the number of rotational brigade combat teams from four to three. Then Trump posted on Truth Social that 5,000 additional troops would go to Poland, which left the final picture unclear.
Planned long-range strike deployments to Germany, including Tomahawk and SM-6 missiles, were halted as well.
Options on the table
Media reports describe deeper cuts under study. Fighter aircraft assigned to NATO plans would drop from about 150 to 100. Eight tanker aircraft would leave. Maritime reconnaissance planes would fall from 26 to 15, and bomber task forces in Europe from two to one. A carrier and its strike group could be redeployed, with fewer submarines and surface combatants. Many of these proposals are still under review rather than final policy.
Europe’s answer
European governments did not wait. NATO estimates that European allies and Canada raised annual defense spending by roughly 20 percent in 2025. NATO Secretary General Mark Rutte said in June 2026 that allies had filled “most” of the gaps left by smaller U.S. contributions. General Alexus Grynkewich, the Supreme Allied Commander Europe, later said the gaps in NATO’s defense plans had been “largely filled.”
The July 2026 Ankara Summit produced concrete projects. Allies announced a multinational A400M airlift initiative and added Airbus A330 MRTT tankers to the shared fleet. They plan to buy MQ-4C Triton drones and Saab GlobalEye aircraft. Twelve European allies launched a deep precision strike initiative, committing approximately $50 billion over the next decade for systems that can hit targets from 300 km to more than 2,000 km.
Gaps remain. Command-and-control networks, intelligence fusion and advanced air and missile defense still lean on U.S. capabilities, and CSIS says industrial capacity, not political will, is the main brake on faster progress. Production of air-defense interceptors, precision-guided munitions and long-range strike systems is constrained. Both NATO and the EU have started programs to expand output and speed up joint purchasing, among them the EU’s SAFE program and ReArm Europe/Readiness 2030.
Sources
- US kicks off review of its force posture in Europe
- The Europe Force Posture Review and the Transition to NATO 3.0
