Dan Drollette Jr., Bulletin of the Atomic Scientists, October 30, 2025 —
President Donald Trump wrote on Truth Social, his social media site, that he had instructed the Department of War (formerly the Defense Department) to return to “nuclear testing” — although it’s unclear whether he was referring to testing a nuclear delivery system (such as a rocket) or testing a nuclear explosive device (the actual bomb itself). Those are two very different things that Trump seems to be confused about.
In the words of prominent nuclear weapons expert Hans Kristensen of the Federation of American Scientists (who is one of the lead authors of the “Nuclear Notebook” column, published regularly in the Bulletin of the Atomic Scientists): “It’s hard to know what he means. As usual, he’s unclear, all over the map, and wrong.” Kristensen then goes into detail, debunking a series of Trump’s assertions in his social media post. For instance, Trump’s initial claim that “[t]he United States has more Nuclear Weapons than any other country. This was accomplished, including a complete update and renovation of existing weapons, during my First Term in office…” is simply false.
As Kristensen points out, Russia has more nuclear weapons than the United States. And Trump’s assertion about a “a complete update and renovation of existing weapons” is also flatly wrong. In Kristensen’s words, “The nuke modernization program currently underway was initiated by Obama, Trump didn’t finish it, and it will continue for another two decades.”
Click on the image above to see the full, complete string of Kristensen’s linked posts.
And as Kristensen notes, the US already tests its missiles (without nuclear payloads) to ensure that they can launch safely and correctly: “If by testing he [Trump] means nuclear explosive testing, that would be reckless, probably not possible for 18 months, would cost money that Congress would have to approve, and it would certainly trigger Russian and Chinese and likely also India/Pakistan nuclear tests. Unlike the US, all these countries would have much to gain by restarting test testing. There have been occasional rumors that Russia/China may have conducted very small-yield tests, I’m not aware of any reports that they have conducted significant nuclear test explosions.”
The process of resuming testing would be nowhere near as swift as Trump suggests; the White House would have to direct the US Energy Department to order our national nuclear laboratories to start preparing for a nuclear warhead test. And since the United States doesn’t currently have a nuclear weapons test explosion program, Congress would have to appropriate the money.
Furthermore, Kristensen notes “[i]t would be expensive and take time: a simple explosion is 6-10 months, a fully instrumented test in 24-36 months, and a test to develop a new nuclear warhead is about 60 months.”
Just in case Trump is indeed talking about testing a nuclear explosive device, now is probably a good time to look back at the Bulletin’s March 2024 issue, “A return to nuclear testing?”, which lays out the many negative impacts of nuclear testing. In that issue, veteran national security reporter Walter Pincus explains exactly what those who live in a place chosen for testing experience in “The horrors of nuclear weapons testing.” People today seem to have forgotten—if they ever knew—what a single nuclear weapon can do. The inhabitants of the Marshall Islands, whose home was turned into a nuclear proving ground, have certainly never forgotten.
Beyond that, the reasons for preserving a ban on nuclear tests are many—even though Russia, China, and the United States have been keeping their test sites ready for a potential resumption of full-scale tests of nuclear explosive devices, just in case. Eminent researcher Pavel Podvig delves into this in detail in his Bulletin essay, “Preserving the nuclear test ban after Russia revoked its CTBT ratification.”
And one thing that seems to get overlooked is that the United States has benefited from a test ban as much as anyone else. Consequently, bringing the Comprehensive Nuclear Test Ban Treaty into force would lock in an American advantage in nuclear knowledge and expertise and hinder other states from developing more sophisticated nuclear arms, as Stanford University expert Steven Pifer notes in “The logic for US ratification of the Comprehensive Nuclear Test Ban Treaty.”
