**NATO’s Article 5 collective-defense clause has not been invoked since the 2001 response to the September 11 attacks, and current conditions point strongly against any invocation before 2027.** The Russia-Ukraine war continues without direct strikes on Alliance territory that would meet the armed-attack threshold, while NATO has reinforced its eastern flank with additional battlegroups, enhanced air defenses, and elevated defense spending targets. The July 2026 Ankara summit produced a formal reaffirmation of an “ironclad commitment” to Article 5 by all 32 members, including the United States, even amid debates over burden-sharing and U.S. conventional force posture adjustments. European allies are accelerating their own capabilities ahead of a 2027 planning horizon, further reducing the near-term likelihood of an uncontained incident crossing into Article 5 territory. Hybrid probes, such as prior airspace violations, have prompted consultations and operational responses but have not triggered the clause. With deterrence intact and no scheduled events or verified escalations in the immediate window, traders assign very high probability to no invocation.