Dylan Spaulding

Should America resume nuclear tests? America’s last nuclear detonation was nothing special. Smaller than the bomb that killed 73,000 people in Nagasaki, it exploded 1,397 feet below the Nevada desert. It shook the ground, created a shall...

What advocates for testing don't realize is that US scientific achievements (e.g. fusion at NIF) are a surrogate demonstration of the credibiliity of the nuclear stockpile and allow better understanding of the underlying physics than a mushroom cloud.

Posting for no apparent reason whatsoever.....

Seeking a New Moral Compass on Nuclear Weapons Aboard the Golden Rule A sailboat that symbolized anti-nuclear activism in the late 1950s has been restored as a reminder of the need for arms control.

A new film was just released for Veteran's Day about the 1958 voyage of the Golden Rule to protest nuclear tests in the Pacific. I was recently fortunate to sail aboard the boat and wrote about that experience. You can watch the film and check out the blog here:

www.youtube.com/watch?v=DhrS...

This also reminds me of a comic strip in which a nuclear engineer is worried they've made a mistake and their colleague asks "what's the worst that could happen?" They reply "millions of people could survive".

Would be embarrassing, indeed, but declarative tests also come with a host of other consequences, almost all of which are not in the US's favor.

@dtc94133.bsky.social - refurbs and life extensions do involve replacing DT reservoirs and other components but also, subcrits can be instrumented to a degree that wasn't possible pre 1992. I argue that the US can better understand the processes (therefore reliability) today than during testing days

“If they wanted to just make the ground shake, you could probably do that sooner, but there wouldn’t be a purpose to the test beyond political signaling,” the source said. Exactly what I've been saying:

Exclusive: Department of Energy officials to meet with White House to tamp down Trump’s idea of explosive nuclear testing | CNN Politics Top energy and nuclear officials in the Trump administration are planning to meet with the White House and National Security Council in the coming days to dissuade President Donald Trump from resuming...

This entire saga over Trump's suggestion to test only demonstrates how dangerously uninformed he is about his own nuclear arsenal. That, in and of itself, is a national security threat that needs acknowledging.

Declassified cable reinforces proliferation concerns about high-assay low-enriched uranium fuel The declassified document reveals an urgent need for an international review of the proliferation risks of HALEU.

From my colleague, @nucsafetyucs.bsky.social at @ucs.org, "without appropriate constraints, large-scale production and use of HALEU may greatly increase the risks of nuclear proliferation and terrorism" and it seems this was recognized decades ago:

This is a really tragic loss.

What Rosalind Franklin truly contributed to the discovery of DNA’s structure Franklin was no victim in how the DNA double helix was solved. An overlooked letter and an unpublished news article, both written in 1953, reveal that she was an equal player.

Today seems like a good time to remember Rosalind Franklin, without whom, James Watson may have never have gained the notoriety his obituaries proclaim. Bonus: she didn't use genetics as a guise to promote the kind of racist and sexist ideas Watson did.

Will Politics Put More People’s Health at Risk from Radiation Exposure? The Trump administration's attack on the science underlying regulations that protect the public from the health risks of radiation exposure could affect many government rules.

My brilliant @ucs.org colleague Chanese Forté interviews two other brilliant folks, Dr. Jan Beyea, and @nucsafetyucs.bsky.social, on the Trump administration's moves to undermine sensible, science-based limits on radiation exposure. Team Trump seems to wants to promote nuclear power at any cost.

What Trump’s nuclear weapons tests could mean for America and the world Trump’s command risks a global arms race while the Doomsday clock ticks closer than ever to midnight, experts say

Any “scientifically useful” test would take years, according to Dylan Spaulding, senior scientist with the Union of Concerned Scientists’ Global Security Program. “Anything shorter than that would be nothing more than dangerous political showmanship and would not allow collection of useful data.”

Experts warn explosive nuclear testing would trigger escalation - UPI.com President Donald Trump's calls to ramp up nuclear weapons testing have put nuclear watchdogs on alert while experts say the United States has little to gain.

Thanks to UPI for reaching out to me for this story on Trump's nuclear testing rhetoric. Its still not clear the admin understands how high the stake are. The US has everything to lose and virtually nothing to gain by returning to explosive nuclear testing.

Language models cannot reliably distinguish belief from knowledge and fact - Nature Machine Intelligence Suzgun et al. find that current large language models cannot reliably distinguish between belief, knowledge and fact, raising concerns for their use in healthcare, law and journalism, where such disti...

ChatGPT and other AI chatbots cannot reliably distinguish belief from knowledge and fact, according to this new study. Seems important! www.nature.com/articles/s42...

FWIW, VADM Correll (nominee to lead USSTRATCOM) a few days ago to SASC: "Neither China or Russia has conducted a nuclear explosive test, so I’m not reading anything into it or reading anything out. To my knowledge, the last explosive nuclear testing was by North Korea, or DPRK, and that was in 2017"

November 1, 2025 Yesterday I wrote that President Donald J.

“They were careless people,” Fitzgerald wrote, “they smashed up things and creatures and then retreated back into their money or their vast carelessness or whatever it was that kept them together, and let other people clean up the mess they had made.”

The symbolism is too perfect.

What Trump’s nuclear weapons tests could mean for America and the world Trump’s command risks a global arms race while the Doomsday clock ticks closer than ever to midnight, experts say

Excellent piece on Trump's call to resume nuclear testing in The Independent (and not just because is cites me & my @ucs.org colleague @dkspaulding.bsky.social).
BLUF for Trump, as duly noted by our @nuclearban.bsky.social colleague: Melissa Park: "This is no way to win the Nobel Peace Prize."

China Has the Most to Gain from New Nuclear Tests President Trump announced the United States will resume nuclear testing, but if China follows suit, he may regret this decision.

In this piece, my colleague @gkucs.bsky.social discusses the implications and potential Chinese response to Trump's recent suggestion that the US will resume nuclear testing. China has much more to gain from testing than the US and its not clear POTUS knows this. @ucs.org #Nukesky

Murmurs from this admin about nuclear testing are not new, which is why earlier this year, we published this piece in the @thebulletin.org on why a rapid test as a show of force is a BAD, BAD idea.

Putting Science to Work for Security: A Call to Prevent Nuclear Testing Scientists have a role to play in protecting our collective future by speaking in opposition to a resumption of nuclear weapons testing.

Earlier this year, Nevada passed a (bipartisan!) resolution, AJR 13, opposing the resumption of nuclear testing. Nuclear testing comes with potential harms to people and the environment and NV doesn't want it. Here's what I told the state legislature about why any return to testing is a bad idea:

What is Russia's Burevestnik missile? President Vladimir Putin said on Sunday that Russia had tested its Burevestnik nuclear-powered cruise missile. Here are some key facts about the weapon.

(2/n) This is likely motivated by a recent Russian test of a new, nuclear-capable cruise missile called Burevestnik. Testing a missile is different than testing a nuclear weapon.

US Navy test-fires unarmed Trident nuclear-capable missiles The U.S. Navy carried out four scheduled unarmed missile tests of the Trident II D5LE off the coast of Florida last week.

(3/n) Strangely, the directive is aimed at the DoW [formerly DoD] but they aren’t responsible for testing nuclear weapons, just the systems that carry them. The US has done this as recently as last month.

(4/n) No one knows what Trump means by “testing on an equal basis”, but the US already DOES conduct all types of tests that other nuclear states do. Neither Russia nor China have conducted full-scale nuclear tests since 1990 and 1996, respectively. The last US test was in 1992.

(5/n) Both Russia and the United States have abided by a Comprehensive Test Ban since the 1990’s and have not carried out full-scale nuclear tests since then. The US never officially ratified the treaty and Russia withdrew in 2023.

(6/n) If Trump is actually referring to underground testing, its not so simple. The US cannot conduct even a rudimentary test within ~6 months and even that is optimistic. Such a test would not provide useful information about the stockpile.

Why it would be a bad idea for the Trump administration to conduct a "rapid" nuclear test The goal of conducting a fast-tracked nuclear test can only be political, not scientific. The United States has much to lose and little to gain from a new test.

(7/n) A scientifically useful test would take several years to prepare, instrument, and conduct. Anything shorter than that would be nothing more than dangerous political showmanship and would not allow collection of useful data.

On The Future of Nuclear Testing in America A strong and meaningful test ban would come at virtually no strategic cost since the US has so little to gain from renewed testing.

(8/n) As I’ve written before, there is little to no incentive for the US to return to full-scale nuclear testing and the costs of doing so FAR outweigh any potential technical benefit. The US would sacrifice its existing advantage and open the gates for adversaries to do the same.

The president has ordered the “Department of War” to immediately resume nuclear testing. Here’s a thread on what you need to know (1/n)

A House of Dynamite Gets It Right—But Here’s the Full Picture The Pentagon is wrong to attack the movie for being inaccurate. We cannot rely on missile defense systems to protect us from nuclear destruction.

The Pentagon objects to the depiction of missile defense in House of Dynamite but, according to my colleague, @lauraegrego.bsky.social, "the GMD system has not been shown to work under realistic conditions...[its] test program is like T-ball practice when the real world is major league baseball."