A treaty that prevented the US and Russia from expanding their nuclear weapons arsenals expired on Thursday, dismantling a major guardrail against a renewed arms race between the rival powers.
The Strategic Arms Reduction Treaty, commonly known as New START, required the two countries to restrict their nuclear warheads to 1,550 and missiles and bombers capable of delivering them to 700. These included weapons deployed and ready for use.
The US and Russia together hold nearly 85 per cent of the world’s strategic nuclear weapons and the expiration of the treaty, signed in 2010, threatens to launch the kind of unconstrained arms race that defined the Cold War. It may also prompt other nuclear and nuclear-adjacent nations to expand their arsenals at the very moment the world is engulfed in a series of escalating conflicts and trigger-point tensions.
Efforts are underway to salvage the situation, with both the White House and the Kremlin hinting at some form of deal to observe the treaty even after its expiration. And even if nothing is agreed on paper, other forms of constraint mean a sudden and unfettered new nuclear arms race is considered unlikely.
In a post on his Truth Social platform, US president Donald Trump said on Thursday: “We should have our nuclear experts work on a new, improved, and modernised treaty that can last long into the future.” This, he added, was preferable to extending New START, “a badly negotiated deal by the United States that, aside from everything else, is being grossly violated”.
Kremlin spokesperson Dmitry Peskov said Moscow viewed the end of the nuclear pact “negatively” and regretted it, but was ready for a dialogue with Washington.
The foreign ministry, meanwhile, said that Russia “remains ready to take decisive military-technical measures to counter potential additional threats to national security”, suggesting a readiness to bolster its nuclear arsenal if necessary.
In spite of the treaty’s expiration, experts say, some smaller guardrails around arms control are still in place, even if there are no limits on total numbers of warheads now.
Ankit Panda, author of The New Nuclear Age: At the Precipice of Armageddon, said it was impossible to compare the current rate of nuclear material production with the situation during the Cold War.
“Just to put numbers on what we are talking about with industrial constraints, the United States does have non-deployed warheads in reserve – about 1,900 or so. But in terms of the ability to competitively arms race, it is currently unable to produce what is going to be a target for 30 plutonium pits. The goal is to reach that by 2028,” he said.
“At the height of the Cold War of the 1960s, the United States was producing around 2,000 plutonium pits.”
Panda said that unlike during the Cold War, there are now deals still in force to prevent an inadvertent nuclear war between the US and Russia. These include the 1988 agreement on ballistic missile launch notifications and the 1989 deal on the notification of strategic exercises.
“It’s really important to recall that while we are entering, for the first time in five decades, a world where there’s no quantitative caps on the size of the forces or on plans for reductions, the US and Russia are not going back to zero,” he said.
In 2017, Mikhail Gorbachev warned that the world could be headed for a new Cold War as tensions between Russia and the West rose. The former Soviet Union leader accused the US and its partners of moving away from peace agreements on nuclear weapons and other central issues.
Matt Korda, associate director of the Nuclear Information Project at the Federation of American Scientists, said that such a scenario would be the worst case. He argued, however, that neither Mr Trump nor his Russian counterpart Vladimir Putin could afford nuclear expansion, pointing to the overtaxed nuclear enterprises of the US.
“I don’t think it’s really a surprise that Putin proposed this sort of one-year maintenance deal to maintain the New START central limits. It’s not in Russia’s interest to dramatically accelerate this ongoing arms race while its current modernisation programmes are going so poorly and while its industrial capacity is tied up in Ukraine,” he said.
