nuclear-news

If the US resumes nuclear weapons testing, this would be extremely dangerous for humanity

Tilman Ruff, Honorary Principal Fellow, School of Population and Global Health, The University of Melbourne, October 30, 2025, https://theconversation.com/if-the-us-resumes-nuclear-weapons-testing-this-would-be-extremely-dangerous-for-humanity-268661?utm_medium=email&utm_campaign=Latest%20from%20The%20Conversation%20for%20October%2031%202025%20-%203566936381&utm_content=Latest%20from%20The%20Conversation%20for%20October%2031%202025%20-%203566936381+CID_7ad11048cc6a12b2fcdd641252fbcae9&utm_source=campaign_monitor&utm_term=If%20the%20US%20resumes%20nuclear%20weapons%20testing%20this%20would%20be%20extremely%20dangerous%20for%20humanity

US President Donald Trump has instructed the Pentagon to resume nuclear weapons testing immediately, “on an equal basis” with other countries’ testing programs.

If Trump is referring to the resumption of explosive nuclear testing, this would be an extremely unfortunate, regrettable step by the United States.

It would almost inevitably be followed by tit-for-tat reciprocal announcements by other nuclear-armed states, particularly Russia and China, and cement an accelerating arms race that puts us all in great jeopardy.

It would also create profound risks of radioactive fallout globally. Even if such nuclear tests are conducted underground, this poses a risk in terms of the possible release and venting of radioactive materials, as well as the potential leakage into groundwater.

The Comprehensive Nuclear Test Ban Treaty has been signed by 187 states – it’s one of the most widely supported disarmament treaties in the world.

The US signed the treaty decades ago, but has yet to ratify it. Nonetheless, it is actually legally bound not to violate the spirit and purpose of the treaty while it’s a signatory.

What testing is used for, and why it stopped

In earlier years, the purpose of testing was to understand the effects of nuclear weapons – for example, the blast damage at different distances, which provides confidence around destroying a given military target.

Understanding the consequences of nuclear weapons helps militaries plan their use, and to some extent, protect their own military equipment and people from the possible use of nuclear weapons by adversaries.

But since the end of the second world war, states have mostly used testing as part of the development of new weapons designs. There have been a very large number of tests, more than 2,000, mostly seeking to understand how these new weapons work.

The huge environmental and health problems caused by nuclear testing prompted nations to agree a moratorium on atmospheric testing for a couple of years in the early 1960s. In 1963, the Partial Test Ban Treaty banned nuclear tests in all environments except underground.

Since then, nuclear-armed states have stopped explosively testing at different times. The US stopped in 1992, while France stopped in 1996. China and Russia also aren’t known to have conducted any tests since the 1990s. North Korea is the only state to have openly tested a nuclear weapon this century, most recently in 2017.

These stoppages came in the 1990s for a reason: by that time, it became possible to test new nuclear weapon designs reliably through technical and computer developments, without having to actually explode them.

So, essentially, the nuclear states, particularly the more advanced ones, stopped when they no longer needed to explosively test new weapon designs to keep modernising their stocks, as they’re still doing.

Worrying levels of nuclear proliferation

There is some good news on the nuclear weapons front. The Treaty on the Prohibition of Nuclear Weapons has now been signed by half the world’s nations. This is a historic treaty that, for the first time, bans nuclear weapons and provides the only internationally agreed framework for their eventual elimination.

With the exception of this significant development, however, everything else has been going badly.

All nine nuclear-armed states (the US, China, Russia, France, the United Kingdom, India, Pakistan, North Korea and Israel) are investing unprecedented sums in developing more accurate, stealthier, longer-range, faster, more concealable nuclear weapons.

This potentially lowers the threshold for their use. And it certainly gives no indication these powers are serious about fulfilling their legally binding obligations to disarm under the Nuclear Non-Proliferation Treaty.

Moreover, multiple nuclear-armed states have been involved in recent conflicts in which nuclear threats have been made, most notably Russia and Israel.

Worryingly, we have also seen the numbers of nuclear weapons “available for use” actually start to climb again.

This includes those in military stockpiles, those that have been deployed (linked to delivery systems such as missiles), and those on high alert, which are the ones most prone to accidental use because they can be launched within minutes of a decision to do so. All of these categories are on the increase.

Russia, in particular, has weapons we haven’t seen before, such as a nuclear-powered, nuclear-armed cruise missile that President Vladimir Putin said on Sunday his country has successfully tested. China, too, is embarking on a rapid build-up of nuclear weapons.

And the US has just completed assembling a new nuclear gravity bomb.

A new START treaty also not moving forward

Nearly all of the hard-won treaties that constrained nuclear weapons since the end of the Cold War have been abrogated.

There’s now just one remaining treaty constraining 90% of the world’s nuclear weapons, which are in the hands of the US and Russia. This is the New START Treaty, which is set to expire in February next year.

Putin offered to extend that treaty informally for another year, and Trump has said this is a good idea. But its official end is just four months away, and no actual negotiations on a successor treaty have begun.

The US has also said China needs to be involved in the successor treaty, which would make it enormously more complicated. China has not expressed a willingness to be part of the process.

Whether anything will be negotiated to maintain these restraints beyond February is unclear. None of the nuclear-armed states are negotiating any other new treaties, either.

All of this means the Doomsday Clock – one of the most authoritative and best-known assessments of the existential threats facing the world – has moved forward this year further than it has ever done before.

It’s really an extraordinarily dangerous time in history.

November 1, 2025 Posted by Christina Macpherson | USA, weapons and war | Leave a comment

The experts respond to Trump’s proposal to “start testing our Nuclear Weapons on an equal basis”

even if China was to up the number of its warheads dramatically, that would still amount to less than a third of what the United States and Russia each already have.

By Dan Drollette Jr | October 30, 2025, https://thebulletin.org/2025/10/the-experts-respond-to-trumps-proposal-to-start-testing-our-nuclear-weapons-on-an-equal-basis/

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 or testing a nuclear explosive device. 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.”

Kristensen then proceeds for eight linked posts to correct or clarify the many other misstatements made by the president in Trump’s Truth Social post. For example, even if China was to up the number of its warheads dramatically, that would still amount to less than a third of what the United States and Russia each already have.

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, it’s 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 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.”

October 31, 2025 Posted by Christina Macpherson | USA, weapons and war | Leave a comment