Russia-US nuclear pact is about to end and we won't see another
After the New START treaty expires in February, there will be no cap on the number of US and Russian nuclear weapons - but some are sceptical about whether the deal actually made the world safer
Russia shows off its weaponry at a military parade in Moscow
Mikhail Svetlov/Getty Images
In February 2026, for the first time in decades, there will be no active treaty limiting the size of the US and Russian nuclear arsenals. Experts are divided on whether the New START treaty genuinely made the world safer, but there is far more agreement on one thing: a replacement is unlikely.
The US and Russia first agreed to place limits on their nuclear weapons and allow each to inspect the other’s stockpiles with the START I treaty in 1991, and this was succeeded by New START in 2011. In 2021, Joe Biden and Vladimir Putin agreed to extend the treaty by five years. It is now due to expire on 5 February and talks on a replacement have faltered.
Tension between Russia and the US had already been ratcheting up when the former staged a full-scale invasion of Ukraine in 2022. Just months later, Russia pulled out of weapons inspections, prompting the US to reciprocate. Now, there is talk from both states about a resumption of nuclear testing – a bellicose bit of theatre with no practical purpose. A replacement for New START seems more unlikely now than ever.
Mark Bell at the University of Minnesota says a new treaty that caps US weapons at a similar number to Russia is unlikely to appeal to the US, which fears that it needs enough to deter both Russia and China at once. China has 600 nuclear weapons, far fewer than the 5000-plus that the US and Russia both hold, but it is growing its arsenal rapidly. Meanwhile, Russia is unlikely to accept a cap that follows this argument and seeks to allow it fewer bombs than the US. And China won’t want to be dragged into a new deal if it caps bombs at current levels, preventing eventual parity with Russia and the US. Treaties are never easy, but this is a knotty starting point, says Bell.
START I and New START have broadly been seen as a success. They certainly aren’t perfect, but they are a pragmatic and stabilising influence. But Bell is sceptical about whether they have actually done much to make the world safer. “Did they save both of the superpowers a bit of money? Maybe. Did they provide a forum that was useful for cooperation? Yes. But did they fundamentally change the probability of war? I don’t think so,” he says.
With or without a treaty, there will always be a real risk of nuclear war, says Bell. In many ways, the threat of mutually assured destruction is the best insurance we have now that the atom has been split, and it is the unthinkable results of nuclear conflict rather than treaties that actually prevent wars, he says. “The stabilising effect comes from the danger, and you can’t get rid of that. That’s a feature, not a bug, of nuclear deterrence,” he says.