**NATO has not faced a direct armed attack on member territory since the 9/11 invocation of Article 5, and recent developments reinforce the low probability of such an event before 2027.** NATO Secretary General Mark Rutte has emphasized the alliance’s deliberate ambiguity regarding the exact threshold for collective defense, noting that hybrid actions—such as drone incursions, sabotage, cyberattacks, and undersea cable damage attributed to Russia—have remained below that line and elicited measured responses short of Article 5. European allies have increased defense spending and force commitments to offset reduced U.S. posture under the current administration, while NATO maintains detailed contingency plans for the eastern flank. Intelligence assessments point to a potential Russian testing window opening in 2027 rather than imminently, and no conventional strikes on allied soil or factories have occurred that would clearly trigger the clause. Traders price the outcome accordingly, viewing sustained sub-threshold pressure and alliance deterrence as the prevailing dynamic through the end of 2026.