From umbrella to arsenal: boosting Europe's nuclear deterrence

Europe is entering its most dangerous decade since the Cold War. The post-Cold War peace has been shattered by Russia’s full-scale invasion of Ukraine and an escalating campaign of hybrid aggression aimed at destabilising the continent. Military and intelligence leaders are sounding the alarm with growing urgency: within the next three to five years, Russia could be in shape to launch a direct attack on a NATO member, plunging the Alliance into open war.

To prevent such a catastrophe, deterrence must remain the bedrock of Europe’s defence strategy. In response to these threats, frontline states along NATO’s eastern and northern flanks have begun unprecedented rearmament efforts. However, deterrence without a nuclear dimension is incomplete—and, in the face of a nuclear-armed adversary, potentially ineffective.

Nuclear deterrence has long been central to European security. During the Cold War, it was the US nuclear umbrella, combined with forward-deployed conventional forces, that held the Soviet threat in check. Today, however, cracks are emerging in the transatlantic bond, as the current US administration’s mixed signals on NATO commitments have deepened European anxieties about the reliability of American security guarantees.

Even more concerning, Russia has developed and deployed new intermediate-range nuclear missiles on NATO’s doorstep, while intensifying its nuclear sabre-rattling through explicit threats and provocative rhetoric aimed at undermining allied resolve.

Against this backdrop, Europe must confront a pressing question: how can it strengthen its own nuclear arsenal to ensure a credible deterrent against Russia—with or without the backing of the US umbrella?