Traders assign a 91% probability against NATO invoking Article 5 before 2027, reflecting the continued absence of any armed attack on alliance territory that meets the treaty threshold. The Russia-Ukraine conflict has produced airspace incursions and hybrid incidents prompting Article 4 consultations, yet NATO maintains a strict interpretation requiring consensus on direct aggression. Forward deployments along the eastern flank, increased exercises, and European efforts to assume greater conventional defense responsibilities by 2027 have reinforced deterrence without escalation. No major diplomatic or military developments in recent months have altered this positioning, consistent with the alliance’s sole historical invocation after the 2001 attacks.