The threat of nuclear weapons is greater than ever. Here’s how international law can help

The outlook for nuclear arms control is desolate in all three of its dimensions – risk reduction, non-proliferation and outright elimination.

The important agreements of the past are dead or on life support.

And the recent behaviour of the actors that matter most – the United States, Russia and China – has fed concerns things can only get worse.

The nine nuclear-armed states possess between them more than 12,200 nuclear warheads, with a combined destructive capacity of more than 145,000 Hiroshima bombs.

Some 9,000 of these are militarily active or deployed.

Alarmingly, some 2,000 US and Russian weapons remain on dangerously high alert, ready to be launched within a decision window for each president, if their country is perceived – rightly or wrongly – to be under nuclear attack, of just four to eight minutes.

The US and Russia, holding between them 90% of the global stockpile, dramatically downsized their inventories after the end of the Cold War.

But that momentum has completely stalled.

Every nuclear-armed state is now modernising or increasing its arsenal.

This is especially true of China, whose inventory has doubled in a few short years to nearly 600 weapons , with new land- and seaborne delivery systems.

More troubling still, the longstanding taboo against the use of nuclear weapons may be weakening, with Russia’s President Vladimir Putin in particular talking up this prospect in the Ukraine war in language not heard since the height of the Cold War.

A number of states are considering using nuclear weapons – especially so-called “tactical” weapons – not just for deterrence but for warfighting.

Read more: Russia’s nuclear strategy in Ukraine isn’t deterrence – it’s terror As agreements die, the threat rises The big arms-control agreements of the past, which – at least between the US and Russia – banned certain systems outright, set constraints on deployments and built confidence through transparency, are now dead.

These include the Anti-Ballistic Missile and Intermediate-range Nuclear Forces treaties.