The Transformation of European Deterrence after the War in Ukraine

The war in Ukraine has marked a structural rupture in Europe’s understanding of deterrence and security. For more than three decades, the continent’s stability had rested on the assumption that the post-1989 order was irreversible and that large-scale conventional warfare was a phenomenon of the past. This belief allowed European states to downsize their armed forces, dismantle reserves, reduce stockpiles, and outsource the ultimate guarantee of their security to the United States. The re-emergence of interstate war, driven by a revisionist power willing to occupy territory and absorb losses on a massive scale, has shattered that confidence. Deterrence is no longer a symbolic notion based on reputation or rhetoric; it has become a measurable capability to fight, endure, and regenerate. The new European challenge is therefore not only military but also political and industrial: deterrence must again be understood as a permanent condition of readiness rather than an episodic crisis response.