After thousands of nuclear weapons tests during the Cold War, we are fortunate to live in a world where every nuclear power except North Korea adheres to the norm opposing explosive nuclear tests. To help achieve this, the United States hasn’t conducted such a test since it declared a voluntary moratorium on the practice in 1992.
The incoming Trump administration will almost certainly try to change that, if it can.
If the United States resumes its nuclear testing program, it will risk a second era of widespread testing around the world that could last a generation, causing unpredictable damage to global peace and security. The best way to prevent this is to mobilize policymakers, “frontline” communities (those that would be directly affected by explosive tests), scientists, and other activists to oppose further testing. For the next four years, we need to be on alert and prepared to stop the Trump administration from reviving this dangerous and antiquated Cold War relic.
Trump’s allies are hungry for new nuclear tests
A persistent minority of hawkish voices have opposed the US nuclear testing moratorium since it was first passed by Congress in 1992. Many allies of the incoming Trump administration, who advocate for expanding the US nuclear arsenal and developing new nuclear weapons, have called loudly for the resumption of testing. In the final months of the last Trump administration, officials even considered conducting a “rapid” nuclear test in the misguided hope of gaining leverage over international rivals.
Nuclear testing also comes up in the Heritage Foundation’s Project 2025 manifesto, a collection of policy proposals written by many former (and likely future) members of the second Trump administration. Buried among attacks on climate science and public health is a recommendation for the United States to “move to immediate test readiness,” which would make it even easier for the Trump administration to resume explosive nuclear testing. The United States already maintains the ability to conduct new tests at the Nevada Nuclear Security Site. According to the National Nuclear Security Administration (NNSA), it would take as little as 6 to 10 months of preparation to conduct a simple test for “political purposes,” should the president order one.
Nuclear weapons tests are not needed for safety or security
We don’t know when or why the second Trump administration may declare the need for explosive testing—but, whatever the excuse, the United States has no need for it. In the past, these tests were used to learn technical information about the weapons themselves, and proponents of explosive testing argue that additional information is needed to ensure the safety and reliability of nuclear weapons. But technology has advanced a lot since the first such test was conducted in 1945, and we now have more sophisticated ways to assess nuclear weapons besides blowing them up. US national laboratories use sub-critical experiments (i.e., those that do not generate a nuclear yield), advanced computer simulations, materials physics experiments, and forensic monitoring to study and evaluate the nation’s nuclear weapons.
As required by law, the US national laboratories certify to Congress each year that the nuclear stockpile is reliable, confirming that explosive nuclear testing is not necessary.
The dire consequences of nuclear testing would endure for generations
During the early years of the Cold War, hundreds of explosive nuclear tests were conducted above ground or underwater, often on colonized and Indigenous land. The radioactive materials generated by these explosions mixed with debris from the blast, fell to the earth with rain or were spread hundreds of miles by wind, exposing hundreds of thousands of people globally to dangerous levels of radiation.
Future nuclear tests would be conducted at underground test sites, which are designed to contain radioactive material rather than release it freely into the atmosphere. However, the local consequences can still be serious: even underground explosive nuclear tests can result in the contamination of land and water or the leakage of dangerous radionuclides into the atmosphere. Any explosive nuclear test would also be a moral injustice to frontline communities that are still fighting to clean contaminated land and obtain acknowledgment and compensation for cancer, lung disease, and other health problems resulting from the development, testing, and production of nuclear weapons.
Nuclear testing is never simply a scientific exercise; it is also a message to other countries about capability and intention. If the United States resumes nuclear testing, other countries will perceive that as a threat and almost certainly follow suit. Russia has stated it is ready to resume testing at any moment, and China also maintains nuclear testing infrastructure.
For the United States to resume nuclear testing would also undermine the tremendous advantage in nuclear data it has held since the end of the Cold War. The United States conducted 1,030 nuclear tests above and below ground—more than any other nation, including Russia (with 715 total tests). These historic data are a resource that continues to provide scientific insight and understanding of our stockpile and other aspects of nuclear science. Should the United States return to testing for political purposes, we would only be inviting nations with less nuclear knowledge to catch up, squandering a rarely acknowledged outcome of the Cold War arms race.
Nuclear testing bolsters the false perception that nuclear weapons are important to our national security, increases the risk of conflict between countries with nuclear weapons, and allows countries to develop new types of nuclear weapons. It would also damage already fragile international arms control efforts, including the Comprehensive Test Ban Treaty and Nuclear Nonproliferation Treaty. If these international agreements and norms fail, more countries might seek nuclear weapons for themselves.
The stakes are great, so our resolve must be greater
It takes only a matter of minutes for the US president to order a nuclear test from his desk in Washington, DC. It would take a matter of months for that test to be carried out in the desert of Nevada, with absolutely no technical benefit to the nation. But the disastrous consequences could last for generations and reach around the globe. Those of us in the United States have an urgent responsibility to act, not just on our own behalf but on behalf of every community that would be harmed or terrorized by a reckless new era of explosive nuclear testing.
We can expect the second Trump administration, like the first, to issue many challenges to the causes of peace, democracy, and environmental justice. Over the next four years, we will have to fight many battles to preserve progress when we can—and limit the damage when we cannot. Nuclear testing is likely to be one of those fights, and it’s a fight we can win together. But to succeed, we need to start preparing now.