NATO allies have reinforced deterrence along the eastern flank through expanded battlegroups, higher defense spending targets, and the July 2026 Ankara summit declaration reaffirming an “ironclad” Article 5 commitment despite questions over U.S. burden-sharing. U.S. intelligence assessments from August 2026 indicate Russia may probe NATO resolve with hybrid or limited actions through 2029, yet view a clear armed incursion capable of triggering unanimous collective defense as low-probability in the near term while Moscow remains engaged in Ukraine. Recent airspace violations and drone incidents have prompted consultations under Article 4 rather than Article 5, reflecting allied caution against escalation and preference for calibrated responses that preserve unity without crossing the threshold for full invocation before 2027.