Nuclear testing: Why did the US stop and will it lead to a renewed global arms race? Explained

For the first time in more than 30 years, the world’s most powerful nation may be preparing to press the red button again.

President Donald Trump has called for the United States to resume nuclear weapons testing, breaking with three decades of restraint and reigniting fears of a new global arms race.


In a Truth Social post on Wednesday, Trump said America would begin testing its nuclear arsenal “on an equal basis” with Russia and China — claiming both adversaries had already been conducting secret tests. “Russia is second, and China is a distant third, but will be even within five years,” he wrote, adding that he had instructed the “Department of War” to start testing “immediately.”

The statement came just hours before Trump’s high-stakes meeting with Chinese President Xi Jinping, casting a long shadow over diplomatic efforts and unsettling arms control experts.

Why the US stopped testing nuclear bombs?

If carried out, the move would mark a major shift in US policy, ending a voluntary moratorium on explosive nuclear testing that has been in place since 1992. The United States conducted 1,054 nuclear tests between 1945 and 1992, most of them in Nevada, before halting amid growing environmental concerns and Cold War fatigue.

During the 1950s, above-ground tests escalated tensions with the Soviet Union. President Eisenhower announced a pause in testing in 1958, assuming the Soviet Union would reciprocate, Axios reported.

When the Soviets resumed tests in 1961, the US followed suit. In 1963, the US, the United Kingdom and the Soviet Union signed the Partial Nuclear Test Ban Treaty to end tests in the atmosphere, outer space and underwater, driven by environmental concerns and fallout from the Cuban Missile Crisis.

The Threshold Test Ban Treaty of 1974 limited underground tests to yields below 150 kilotons. In 1992, Congress passed a resolution prohibiting underground nuclear tests unless another state conducted one, establishing the current moratorium. President Clinton signed the Comprehensive Test Ban Treaty in 1997, but the Senate rejected ratification on national security grounds. Globally, as of August 2025, 187 state parties have signed the CTBT and 178 have ratified it.

What US can do instead?

Despite the moratorium, US presidents must certify to Congress annually that the nuclear deterrent is safe and effective.

Frank Rose, former NNSA deputy under President Biden, told Axios: “And for every year since the late 1990s, they’ve been able to do that. Why? Because we have a science-based stockpile stewardship program, which includes experiments, simulations, and other things that ensure that we can maintain the weapons without testing.”

He added: “Indeed, because of that program, we actually understand more about how weapons work now than we did at the height of testing.” Both the Department of Energy and the National Nuclear Security Administration have reaffirmed that the US has “no technical reasons” to conduct nuclear tests.

Why the test now?

Trump first floated the idea during his first term but did not carry out any tests; President Biden has also refrained. The renewed call comes amid reports that China and Russia may be skirting the moratorium.

A 2021 State Department report indicated that the US could not rule out tests by those powers, and satellite imagery suggested activity at China’s Lop Nor test site between 2020 and 2024, as per Axios.

Department of State and Defense Intelligence Agency reports allege that Russia might be conducting clandestine tests. To date, North Korea is the only country known to have conducted full-scale nuclear tests in recent years.

Will Trump be able to resume nuclear testing?

Trump’s order for the US to resume nuclear weapons tests has confounded officials and drawn scrutiny from nuclear experts over the safety, feasibility and purpose of kickstarting an effort that has been paused for more than three decades.

The US has signed — but not ratified — the Comprehensive Test Ban Treaty, leaving President Trump free under law to resume nuclear testing. His announcement has revived painful memories of the Cold War era, when open-air detonations sickened thousands across the American West. Lawmakers from Nevada, which hosted hundreds of tests, condemned the plan as both a public health hazard and a geopolitical provocation that could “lead to World War III," Politico reported.

Experts argue there’s no technical need for renewed testing, noting the US already certifies its nuclear arsenal as safe through advanced simulations and experiments. Each new test could cost $140 million and risk reigniting global tensions. Trump allies, however, claim testing would project strength to China and Russia. Analysts warn such a move could alienate US allies, undermine nuclear restraint, and spark a new arms race just as key arms control treaties near expiration.