The NATO summit in Ankara takes place during a critical transition phase for European security, according to Finnish politician Mika Aaltola. He warns of a "vulnerability window" where NATO's eastern flank is exposed and Russia may be tempted to test Article 5 in practice. Aaltola, an MEP and former head of the Institute of International Affairs in Finland, says that the gap between reduced US commitments and the buildup of European defense capabilities creates a deterrence gap. He believes Vladimir Putin will exploit this through hybrid means such as sabotage, cyberattacks, and drones, without using soldiers. Aaltola emphasizes that the success of the summit depends on how well member states can close this window, and that the reaction from the US will be crucial for the alliance's credibility.