Legal and procedural barriers remain the dominant constraint on any U.S. withdrawal from NATO. A 2023 statute requires Senate advice and consent by two-thirds vote or an act of Congress before the president can suspend, terminate, or withdraw from the alliance, with additional restrictions in the FY2026 NDAA on force posture changes below certain thresholds. President Trump has repeatedly criticized allied defense spending and questioned NATO’s value, including during April 2026 tensions over European support in the Iran conflict, yet stated at the July 2026 Ankara summit that the United States would not leave. The administration has instead pursued incremental drawdowns of U.S. troops, fighter squadrons, tankers, maritime patrol aircraft, and certain command roles to shift primary responsibility to European allies. No formal withdrawal notification has been issued, and midterm elections plus congressional oversight further limit near-term action.