The nuclear arms race is back: What’s driving it and why it matters

Russia’s threats and America’s response Kremlin messaging around potential use of tactical weapons raised anxiety through late 2022.

The cold war’s nuclear shadow had seemed to fade. Arms control deals cut global stockpiles deeply and public fear receded. That comfort is over. Russia’s full-scale invasion of Ukraine in 2022, backed by repeated nuclear hints, dragged atomic deterrence to the centre of geopolitics again. Western governments initially hesitated to arm Kyiv, fearing escalation, then grew bolder as Moscow’s red lines looked less immediate than its rhetoric, the Financial Times reported.

Russia’s threats and America’s response Kremlin messaging around potential use of tactical weapons raised anxiety through late 2022. US and European policymakers weighed every step in Ukraine against the risk of triggering a nuclear response. Over time, the calculus shifted. Western aid expanded, and Ukraine was encouraged to strike targets deeper inside Russia. The episode underlined a sobering truth. Nuclear signalling can restrain adversaries even if the threshold for actual use remains high.

China’s rapid build-up changes the balance Since 2020, China has more than doubled its warhead count and is set to expand again over the next decade. Beijing’s modernisation drive is the most striking part of a wider pattern. All nine nuclear-armed states are upgrading, and several are increasing arsenal sizes. The result is a less predictable strategic landscape than the relatively stable bipolar balance that defined much of the late cold war.

Arms control is fraying when it is most needed Treaties that once limited risks are expiring or being suspended. Verification regimes are weakening. Dialogue channels are thinner. That erosion matters. History is littered with near-misses caused by false alarms, misread signals and human error. During the Cuban missile crisis a Soviet officer refused to authorize a launch. In 1983 another discounted faulty alerts. Robust guardrails helped avert catastrophe. With fewer guardrails, luck plays too large a role.

New proliferation pressures are rising Allies that once relied unquestioningly on the American umbrella are re-examining assumptions. Saudi Arabia, South Korea, Japan, Poland and even Germany figure in speculation about future nuclear choices. Iran’s trajectory remains uncertain. The logic is blunt. If the world’s most powerful democracy looks less predictable abroad, and if conventional aggression by a nuclear state goes unpunished, more countries will consider their own ultimate insurance.

Technology raises fresh dangers Artificial intelligence and cyber tools complicate every stage of the nuclear chain, from design and procurement to command and control. Cheaper, more accessible technologies can lower barriers to entry for would-be proliferators. At the same time, cyber operations threaten to blind, spoof or disable early-warning systems. That combination adds speed and ambiguity to crises that already demand perfect clarity.

Why the outcome in Ukraine will echo globally If Russia is fought to a standstill or pushed back without resort to nuclear use, leaders may conclude that atomic arsenals are blunt instruments, potent for coercion yet constrained in practice. If Russia prevails while the West stands off, the message could be that nuclear status enables conventional aggression against non-nuclear neighbours. Others would take note, and the pressure to proliferate would intensify.

What to watch next Expect renewed debates over extended deterrence, missile defences and trip-wire deployments in Europe and Asia. Watch whether Washington and Moscow can rebuild even minimal risk-reduction channels, and whether Beijing will engage in substantive strategic talks. The priority is not romantic disarmament, it is restoring predictability, rebuilding verification and keeping human judgment, not software glitches, in control of the world’s deadliest weapons.