Barack Obama Sends Warning About Nuclear Arms Race with Russia

Former President Barack Obama is sounding the alarm over the looming expiration of a major nuclear arms control agreement between the United States and Russia, warning that its collapse could trigger a dangerous new arms race between global superpowers.

In a post on X, Obama urged Congress to act before the New START treaty — the last remaining nuclear arms control pact between Washington and Moscow — expires on Thursday. The agreement, which Obama signed in 2010, limits the number of deployed strategic nuclear warheads and requires transparency between the two nations.

“If Congress doesn’t act, the last nuclear arms control treaty between the U.S. and Russia will expire,” Obama wrote. “It would pointlessly wipe out decades of diplomacy, and could spark another arms race that makes the world less safe.”

A White House official told Newsweek last week that President Donald Trump will determine the administration’s next steps on nuclear arms control on his own timeline. Newsweek has also reached out to the Kremlin for comment.

The New START treaty was signed in 2010 by Obama and then–Russian President Dmitry Medvedev during a period when relations between the two countries were being reset. The deal capped each side’s deployed strategic nuclear warheads at 1,550 and allowed for on-site inspections, data exchanges, and notifications.

The treaty was extended once in 2021 under former President Joe Biden, but Russia later suspended its participation, citing U.S. military support for Ukraine. Russian President Vladimir Putin has since suggested an informal, one-year agreement in which both sides would voluntarily adhere to the warhead limits, though the Trump administration has not publicly responded.

Experts say the treaty’s expiration would mark the end of more than 50 years of nuclear arms control cooperation between the world’s two largest nuclear powers, which together possess roughly 87 percent of the globe’s nuclear weapons.

Matt Korda, associate director of the Nuclear Information Project at the Federation of American Scientists, told Newsweek that New START provided rare stability in an otherwise volatile relationship. “It gave transparency and predictability,” he said. “We’re going to be without that now.”

Obama shared a New York Times opinion piece warning that the treaty’s collapse could accelerate a three-way arms race involving the U.S., Russia, and China. The article also noted that the Bulletin of the Atomic Scientists recently moved its symbolic Doomsday Clock closer to midnight, reflecting rising concerns about global catastrophe.

Tilman Ruff, a co-founder of the International Campaign to Abolish Nuclear Weapons, echoed those fears, calling New START “the last guardrail limiting the most destructive weapons ever built.”

Korda added that despite its rhetoric, Russia may not actually benefit from an arms race. He noted that Moscow’s nuclear modernization programs are facing budget overruns and delays, suggesting there may still be incentives on both sides to pursue some form of arms control.