**NATO’s Article 5 collective-defense clause has remained uninvoked since its sole use after 9/11, and traders assign a 94.3% probability that no armed attack triggering it will occur before 2027.** Recent Russian drone incursions into Polish airspace and fighter-jet violations of Estonian territory prompted only Article 4 consultations, followed by enhanced aerial patrols under Operation Eastern Sentry rather than collective-defense activation. NATO has reinforced its eastern flank with additional multinational battlegroups and secured a 2025 summit pledge for 5% GDP defense investment by 2035, measures that analysts link directly to sustained deterrence against direct conventional threats. Russia continues gray-zone and hybrid operations—sabotage, cyberattacks, and airspace probes—explicitly calibrated below the Article 5 threshold, while the Ukraine conflict has not produced cross-border attacks on NATO territory. These patterns, combined with alliance consensus requirements and the historical rarity of invocation, underpin the current market pricing that an Article 5 trigger remains unlikely through the end of 2026.