President Donald Trump’s administration has intensified pressure on NATO allies through a six-month force posture review announced in June 2026 by Defense Secretary Pete Hegseth, with final recommendations due in early November, alongside announced reductions of roughly 5,000 troops from Germany and cuts to assigned aircraft, tankers, and naval assets. Rhetoric around potential full withdrawal has resurfaced amid disputes over European support during U.S. operations related to Iran, yet the 2023 Kaine-Rubio statute requires congressional authorization for treaty exit, and bipartisan lawmakers plus defense interests have signaled strong opposition to any unilateral departure. European allies are accelerating their own defense spending and diversification while preparing for reduced U.S. conventional commitments, though Article 5 reaffirmations and institutional constraints continue to limit the scope of any rapid alliance exit.