From Dan’s notes:

In today’s episode of Critical Conditions, Claire and I discussed what may be the most terrifying decision of the Trump presidency: his plan to resume nuclear testing. We’ve seen recklessness before—the gutting of USAID, the tariff tantrums against allies—but this one feels like a threshold moment. As Claire said at the start, “This is life or death.”

She began by recalling that the United States signed, though never ratified, the Comprehensive Nuclear Test Ban Treaty back in 1996. To make detonations unnecessary, Washington built what became one of the most ambitious scientific programs in modern history—the Stockpile Stewardship and Management program. Its mission was to guarantee the safety and reliability of America’s nuclear deterrent without live tests.

Claire described the staggering scale of that effort: the National Ignition Facility near San Francisco, where hundreds of lasers recreate the pressure and temperature of a thermonuclear blast; the subcritical experiments in Nevada that stop short of chain reaction; and the supercomputers that model detonations down to trillionths of a second. After three decades of such work, she noted, every expert—from the lab directors to the heads of Strategic Command—has said the same thing: our confidence in the stockpile is higher than ever. “Testing again,” she said, “would yield no new information, only instability.” That instability, she argued, is not just technical but psychological. For Russia, China, and North Korea, Trump’s erratic behavior, his public confusion and his obsession with imagined slights will make America look unhinged. “You deter your enemies not by appearing insane but by convincing them you can absorb a shock and respond,” she said. If the man with sole launch authority cannot tell theater from reality, the danger is stumbling into a nuclear war.

My response was simpler, in a way. Trump wants to look like a tough guy, angry that Putin just announced a new missile test and desperate to match it. I don’t think Trump—a man who loves tariffs but doesn’t understand them—can comprehend anything Claire said.

We wondered aloud whether anything could stop it. I noted that Congress technically controls the funding, but that process would take time, and the courts are unlikely to intervene given the treaty’s unratified status. The agencies that might have imposed restraint have been hollowed out—the National Nuclear Security Administration, for instance, is barely functioning after being DOGEd.

From there, the conversation widened, as it always does, to the larger culture that made such madness possible: I said America’s disdain for expertise was becoming a strategic liability.

By the end, the conversation veered toward the other global tremors of the week.

At the APEC meeting—which oddly represents most global trade and basically is a middle finger aimed at Europe—Trump’s false boasts about trade with South Korea fascinated Claire. I focused on the non-deal deal with China.

I also praised Rand Paul and the handful of Senate Republicans who voted down Trump’s tantrumesque Canada tariff addition. It won’t matter much, because the Republican caucus in the House is 100 percent lemmings—but it offered a glimmer of hope. Claire did not dispute me on the lemmings.

Reaching to find a measure of agreement with Trump, I argued that while his hatred of all imports is infantile, the monumental trade deficit with China is actually dire, since the West has created a dangerous dependence.

We ended on something less apocalyptic: the Dutch elections where the far right underperformed. And we resolved that next Monday, we would endeavor to produce a positive, uplifting podcast! Surely there is more good news in the world.

Claire—while we were discussing this, JD Vance blithely remarked to the press that testing the US nuclear arsenal would ensure it actually “functions properly.”

God help us. He’s cheerfully denying all of modern weapons science. He either believes we don’t, in fact, know whether our arsenal “functions properly”—unforgiveable ignorance about the weapons with the power to end organized human existence, ones that could very plausibly, and soon, be under his command—or he’s willing to lie about this, even this, to please the President. But this isn’t a lie about the crowd size at Trump’s inauguration. Suggesting that we don’t know whether our nuclear weapons work is intolerable.

The reason the US hasn’t conducted a live nuclear test since 1992 isn’t that we’ve become cavalier about our deterrent. It’s because we no longer need to. We have complete confidence in the reliability and the deadliness of every weapon in our arsenal. We can model every physical process that takes place in a nuclear explosion with far greater precision than the full-scale tests of the Cold War ever allowed. Our weapons are not only reliable, they are known to be so, and known within margins of error that the Manhattan Project scientists could have scarcely imagined. Livermore, Los Alamos, Sandia, the Nevada complex, and their contractor and academic partners run facilities that model the physics of an imploding plutonium pit, the chemistry of high explosives, the behavior of metals under decades of stress, and a thousand subsidiary processes that scientists in the pre-computer era could only feel in the dark. The confidence we have in our warheads is the product of a deliberate, expensive, and empirically rigorous scientific program that has, for three decades, served precisely the purpose Vice-President Vance claims can only be achieved by exploding bombs.

Testing means breaking the global moratorium that’s held since the early 1990s, effectively ending the Comprehensive Nuclear-Test-Ban Treaty. It means inviting Russia, China, North Korea, India, and Pakistan to follow suit. Within months, the world would once again be awash in radioactive fallout and nuclear brinksmanship.

But by far the most dangerous thing is the way this would raise the temperature of nuclear alert systems. It would do so dramatically. At a moment of heightened tension, a sudden detonation, even if it’s announced in advance, may be misinterpreted by an adversary’s early-warning systems, triggering a launch-on-warning posture and reducing the decision time for nuclear response from minutes to seconds. This means judgment—Donald Trump’s judgment—will be displaced by reflex—Donald Trump’s reflex.

Strategic stability requires predictability. It requres clear channels of communication. It requires the public appearance of credible restraint. Testing undercuts all three. The Comprehensive Test Ban Organization’s global monitoring network exists precisely to detect the moment any state flips the switch. An American detonation would undo decades of progress, give Moscow and Beijing a pretext for parity in provocative behavior, and hand smaller nuclear-armed and aspirant states a glorious permission slip. Moscow and Beijing have more to gain from it than we do—they would learn something by testing; we would not. But none of us have a thing to gain by bringing this world into being.

A nuclear detonation does something no conventional weapon does. In an instant, it converts a sliver of mass into a fireball and radiation pulse, creating a supersonic shock front that collapses buildings and ruptures organs. The mushroom cloud rains radioactive particulates that contaminate land, water, and food for years. The thermal radiation immolates even at a distance; the ionizing radiation will kill you, swiftly; the fallout will kill you, slowly. Electromagnetic pulses from high-altitude pulses can collapse communications and critical infrastructure. The damage is both immediate and persistent: biospheres and the built environment are affected in ways that are qualitatively different from the effects of any other human creation. To treat such an event as “testing”—why, it’s just like routine car maintenance!—is moral flippancy so repulsive it makes me vomit.

The consequences would cascade. A US test would increase the incentive for adversaries to accelerate new delivery systems and adopt operational postures that shorten decision times. It would increase proliferation pressures in volatile regions. It would produce a cascade of policy responses that are not amenable to surgical control: more tests, more radiological insult, more exposure of civilians and soldiers to risks that can’t be remedied with platitudes about “strength.”

On 5:29 a.m. on July 16, 1945, a mushroom cloud rose over the Trinity site in the Jornada del Muerto desert, the name itself an epitaph. Ralph Carlisle Smith, watching from Compania Hill, wrote:

I was staring straight ahead with my open left eye covered by a welder’s glass and my right eye remaining open and uncovered. Suddenly, my right eye was blinded by a light which appeared instantaneously all about without any build up of intensity.

The flash was so bright that observers standing 10,000 yards away were temporarily blinded. It melted sand into trinitite—light green glass, the color of desolation, still faintly radioactive after eighty years. It lies there yet, wind-scoured and silent.

A nuclear explosion is a wholly different category of violence. In the first fractions of a second the weapon converts a tiny fraction of matter into energy and, in doing so, releases more energy in an instant than any chemical combustion ever could. A self-sustaining chain reaction produces an avalanche of energetic particles and photons, and microseconds after ignition, a luminous fireball blooms. Within that sphere, the temperature and radiation density is such that matter is briefly in exotic states: plasmas of stripped atoms, torrents of gamma rays and neutrons that irradiate everything nearby. Milliseconds later the fireball’s expansion drives a supersonic shock front that smashes buildings; it wets and twists the human body in ways ordinary blasts don’t: lungs hemorrhage, eardrums rupture, low-lying structures are lifted and then crushed by reflected overpressures. Thermal radiation, emitted almost instantaneously, ignites combustible material at many kilometers’ distance. People not killed by blast will be immolated by a heat pulse that chars their flesh.

In the desert, witnessing the world’s first manufactured sun, Oppenheimer reached for scripture. He found in the Bhagavad-Gita the only words adequate to express the horror: Now I am become Death, the destroyer of worlds. A nuclear explosion is Genesis played backward. The moment permanently altered our moral imagination. Ever since, every serious statesman who has contemplated the Bomb has grasped that he faces one task more important—far more important—than all the others: ensuring that sun never rises.

Resume testing and you will have weakened non-proliferation, offered license to our rivals, given rise to a rush to build new delivery systems, increased the chance of miscalculation, and produced a strategic environment in which accidents happen, not just possibly, but probably. The century will be governed by reflex and terror.

It is unforgivable. It is unforgivable to support or enable anyone who would do this. At stake is the whole human race, the whole natural world.

Trump’s insistence that our weapons be tested may appear to those who don’t know enough to object to be just one more act of lunacy in an endless procession of them, but it is not. This is different. That it’s come to this is a sign of how profoundly betrayed we’ve been by our Congress, by our Supreme Court, by our fellow citizens, and by every other American institution with the affirmative duty to prevent a madman like this from acquiring a power like that.

Trump now exhibits unmistakable signs of cognitive decline. His public appearances are a miasma of morbid megalomania and confusion. It’s possible that faced with his own mortality, he has resolved to take us all down with us. Yes, he is that insane—and obviously so. Everyone in the world, save for a now-diminishing segment of the American public, can see it. That is precisely the problem. That Trump is the one issuing such an order will only be understood as further evidence that the United States is both dangerously unstable and completely divorced from the deterrence doctrines that allowed us to survive the Cold War.

Our adversaries see a country that is no longer capable of strategic restraint. Our allies see a partner too erratic to trust. In Moscow, Beijing, and even Pyongyang, analysts will interpret this as proof that the American nuclear command chain is hostage to the impulses of a disordered mind. This is precisely the nightmare scenario every serious nuclear strategist since Thomas Schelling has feared.

Trump and those who enable him—and if you are one of them, I mean these words for you—are putting the world at grave risk. That is not hyperbole. To those in Congress who have so far refused to lift a finger to stop this: the time is now. This isn’t a joke. You’ve had your fun. You’ve owned the libs. But this is the abyss. You must stop him. Now.

If you don’t, you stand a good chance of burning in hell. I mean that both literally and figuratively.

For the love of God, stop him.

Declassified nuclear test footage:

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