Fears grow of new nuclear arms race as key U.S.-Russia treaty expires
Today, the world has returned to the mentality of the early Cold War, when uncertainty and acceptance of conflict were high, added Sokov, who is now a senior fellow at the Vienna Center for Disarmament and Non-Proliferation.
“It took the Cuban Missile Crisis to make everyone afraid,” he said, referring to when in the early 1960s the United States deployed nuclear warheads to the United Kingdom, Italy and Turkey, while the then-Soviet Union sent nuclear missiles to Cuba.
This episode, considered the closest to full-scale nuclear war during the Cold War, ushered in an era of regulation. But global interest in arms control has declined in recent decades, Sokov said, as has fear of a nuclear apocalypse.
That makes the loss of New START significant as a tool that ensures some degree of predictability and communication, he said.
In addition to limits on nuclear warheads, the treaty provides for data sharing, mutual compliance checks and a dialogue mechanism to raise and dispel possible misconceptions about what the other side is doing.
Before Moscow suspended New START in 2023, the two sides conducted 328 on-site inspections and exchanged more than 25,000 notifications about each other’s activities, according to the State Department.
Both sides can still use satellite imagery, human intelligence and other forms of restricted data to get a sense of where the other side’s nuclear arsenal is in terms of numbers and capabilities, said Fabian Rene Hoffmann, a researcher at the Oslo Nuclear Project at the University of Oslo.
“But the lack of transparency is of course important, especially in the current low-trust environment,” Hoffmann said.
The expiration means that Russia and the United States no longer have a mechanism to verify each other’s intentions, according to Dmitry Medvedev, who was president of Russia when the treaty was signed in 2010 under President Barack Obama.
Moscow said on Wednesday that it had still not received an official response from Washington to Putin’s offer, accusing him of a “misguided and regrettable” approach, but said it was still open to dialogue. China said Thursday it “regretted” the treaty’s expiration.
Obama also lamented the end of the treaty.
“It would needlessly undo decades of diplomacy and could trigger a new arms race that makes the world less secure,” he said in an article on X.
The Trump administration has said the door is open to negotiations with Russia and China.
“President Trump has repeatedly spoken about the threat nuclear weapons pose to the world and has indicated that he would like to maintain limits on nuclear weapons and involve China in arms control negotiations,” a Trump administration official told NBC News on Monday when asked about the treaty’s expiration.
“Neither fair nor reasonable”
Trump has said he wants to pursue a policy of “denuclearization” with Russia and China. In response, Beijing said it was “neither fair nor reasonable” to ask the country to join nuclear disarmament negotiations when its nuclear arsenal is dwarfed by that of the United States and Russia.
The Pentagon’s annual report presented to Congress in 2025 reveals that Beijing is on track to have more than 1,000 nuclear warheads by 2030, part of what it calls China’s “massive nuclear expansion.”
China’s nuclear development is an example of what happens when there is neither predictability nor control, according to Sokov.
“We know China is growing, but we don’t know to what extent. We don’t know where it will stop,” he said.
A new deal to replace New START could happen without China, Albertson said, but it would have to give the United States and Russia flexibility to be able to adequately respond to Beijing’s nuclear buildup.
