Across European capitals, a quiet reckoning is underway: the continent finds itself engaged in a war it has not formally declared and is not fully prepared to fight. Russia's hybrid campaign — sabotage, covert disruption, infrastructure attacks calibrated to evade collective response — is exposing structural gaps in NATO's deterrence architecture that political will alone cannot close. The warning from defence officials is not one of imminent invasion, but of slow erosion: a security order being worn down at its edges, incident by deniable incident, while the mechanisms for response remain inc