Traders assign an 88.5% probability against NATO invoking Article 5 before 2027 because Russia remains focused on its Ukraine campaign and lacks the assessed capacity for a direct attack on alliance territory in the near term. Recent assessments project Moscow will not achieve readiness for large-scale European conflict before 2030. A Russian drone strike on a Romanian apartment building in late May 2026 prompted NATO condemnation and Article 4 consultations but fell short of the armed-attack threshold required for collective defense. Prior hybrid incidents, including airspace violations in Poland and the Baltics, have similarly triggered consultations without escalation. This pattern, combined with sustained NATO eastern-flank deployments and deterrence signaling, underpins the current market pricing.