Traders assign an 11% implied probability to NATO invoking Article 5 before 2027 because no direct armed attack on alliance territory has occurred to meet the collective defense threshold. Russia’s ongoing conflict with Ukraine and periodic gray-zone probes—such as drone incursions into Poland and airspace violations near Estonia—have prompted only Article 4 consultations. NATO summits have reaffirmed deterrence commitments while European allies increase defense spending under U.S. pressure, including a 2027 target for greater conventional capability leadership. Historical precedent shows invocation only once since 1949, after the 2001 attacks on the United States, and current diplomatic and military postures indicate risks remain below the level that would trigger consensus among members.