The Kremlin’s development of a nuclear-tipped anti-satellite missile and rejection of a new space arms control resolution at the United Nations – both denounced by White House National Security Advisor Jake Sullivan – could ultimately spark a great-power conflict, say defense experts across U.S. universities, think tanks and the American military.
If Russia launches a nuclear-armed ASAT, designed to perpetually circle the globe and potentially challenge the satellites of NATO allies aiding besieged Ukraine, the two sides will move closer to direct confrontation, these experts say.
Defense scholars have been testing nuclear war-game models that predict how the detonation of a warhead in low Earth orbit could play out, projecting the potential casualties in terms of satellites, human spacecraft, space stations and their pilots.
If Russia were to detonate a relatively powerful nuclear bomb at the same altitude and in the vicinity of the International Space Station or the Chinese Space Station, “there would be grave dangers to the astronauts,” says Victoria Samson, Chief Director, Space Security and Stability, at Washington’s Secure World Foundation.
These astronauts “might require an emergency evacuation,” but their docked space capsules could also be damaged by the explosion, she told me in an interview.
Samson points to a massive study conducted by the Pentagon’s Defense Threat Reduction Agency, whose experts used sophisticated computer modeling to examine “the potential damage to satellites from high altitude nuclear detonations.”
Conducting a series of simulated nuclear explosions at varying altitudes with increasingly powerful warheads, the defense agency scholars reported they tested “twenty-one trial nuclear events with varying yields and locations” that ranged from low Earth orbit to geosynchronous orbit.
They discovered the detonation of a 5000 kiloton warhead at an altitude of 200 kilometers – near the International Space Station’s orbit – inflicted “severe damage on the ISS.”
“More significantly,” they reported, “this exposure would cause radiation sickness to the astronauts within approximately one hour and a 90% probability of death within 2-3 hours.”
That means spacefarers aboard the blasted outpost – the ISS or the Chinese Station – would require split-second evacuation after a nuclear burst.
Russian President Vladimir Putin has denied overseeing a secret project to build a new nuclear ASAT. Stationing nuclear weapons in space would be prohibited by the Outer Space Treaty, a UN pact that Moscow has ratified, Samson says.
But Russian weapons designers decades ago developed a missile defense interceptor, fitted with a nuclear warhead, initially aimed at shooting down an enemy’s intercontinental ballistic missiles, Samson says.
That interceptor might be adapted into a devastating ASAT.
To test Russia’s adherence to the Outer Space Treaty, the U.S., Japan and 60+ cosponsors introduced a resolution at the UN Security Council in April calling on all nations to reaffirm their support for the treaty, and to pledge not to deploy any space-based nuclear weapons.
Russia’s envoy to the UN abruptly vetoed the resolution.
From the White House, Jake Sullivan condemned the veto and Moscow’s rebuff of the call by the resolution’s world-spanning backers to avert a space arms race.
“The United States assesses that Russia is developing a new satellite carrying a nuclear device,” Sullivan declared. “We have heard President Putin say publicly that Russia has no intention of deploying nuclear weapons in space. If that were the case, Russia would not have vetoed this resolution.”
Detonating a thermonuclear bomb in low Earth orbit could, in a flash, destroy vast clusters of satellites, according to a former nuclear researcher at the Defense Threat Reduction Agency, Lt. Col. Robert Vincent.
In a project codenamed Starfish Prime, Vincent reported in a research article, Pentagon leaders who staged a 1962 test were astonished to discover: “Even one high altitude nuclear detonation is particularly effective at destroying satellites.”
“Not only were satellites in the line of sight destroyed, but even satellites on the other side of Earth were damaged and rendered inoperable,” Vincent, now a professor of advanced physics at the U.S. Air Force Academy, wrote in a prescient prediction of nuclear clashes in space two years before American intelligence agencies uncovered evidence of Russia’s clandestine rush to produce a nuclear-armed orbiter.
Vincent posited that countries whose satellites have come under nuclear attack would face an intense dilemma in formulating a response that doesn’t involve further use of atomic weaponry or spiral into a great-power clash – in the heavens or across the Earth.
He reported the Cold War super-bomb “Starfish Prime damaged or destroyed roughly one third of all satellites in low Earth orbit at the time.”
“There are currently around 5,000 satellites in low Earth orbit,” Mark Massa, deputy director for strategic forces policy at the Atlantic Council, told me in an interview.
Blasting this high-traffic region of space with a high-yield nuclear device, he says, would damage thousands of civilian satellites, launched by an assemblage of spacefaring nations almost as diverse as the UN.
Since Russia launched its blitzkrieg against democratic Ukraine, Putin’s emissaries to the UN have repeatedly threatened to begin shooting down SpaceX satellites, which have beamed broadband internet coverage to the embattled country.
Astrophysicist Joel Primack, Distinguished Professor of Physics Emeritus at the University of California, Santa Cruz, told me in an interview: “If ~1000 Starlink satellites were explosively destroyed, a debris chain reaction would create a lethal debris field” – a giant and deathly halo of “tiny missiles” that circles the Earth for generations into the future.
Spenser Warren, an expert on Moscow’s new-millennium race to modernize its nuclear arsenal, said there could be a range of Russian rationales for stationing atomic arms in orbit.
The most ominous objective, he told me, would be to give Putin the capability to launch a preemptive nuclear strike against an adversary. The Russian ASAT could be deployed to stage a surprise attack that destroys an enemy’s nuclear command and control satellites, including missile tracking sensors, in advance of a full-scale nuclear “first strike,” says Warren, a postdoctoral fellow at the University of California Institute on Global Conflict and Cooperation.
If the Russian weapon were rocketed into orbit, the U.S., Britain and other NATO nations Putin has already threatened with nuclear strikes would have no way of ascertaining whether the spacecraft was aimed at destroying their strategic command satellites, adds Warren, who is now expanding his doctoral thesis, “Russian Strategic Nuclear Modernization Under Vladimir Putin,” into a book.
Rather than tolerate having its all-important strategic satellites under constant threat of attack by Russia’s nuclear ASAT, the U.S. might opt to destroy Moscow’s orbital missile with a conventional ASAT, Warren predicts.
There would be no possibility of accidentally detonating the Russian nuclear warhead by hitting it with a ground-launched American ASAT, he told me in an interview.
“It is possible to strike a nuclear device with a conventional kinetic kill vehicle without causing a nuclear detonation,” he explains.
But to destroy a Russian spacecraft bearing a plutonium bomb, the U.S. government would first have to navigate a labyrinth of key UN Charter obligations and other rules of international law, says Professor Jack Beard, one of the world’s leading experts on the UN treaties governing space defense.
Moscow’s nuclear ASAT stationed in space would unquestionably violate the Outer Space Treaty, but that treaty does not include any enforcement mechanisms, he told me. Russia’s invasion of Ukraine, and any use of force tied to that invasion, violates Article 2 of the UN Charter, a basic building block of the entire UN system, he adds.
But to justify the American use of force against even an illegally stationed Russian weapon of mass destruction, orbiting the Earth, Professor Beard adds, the U.S. would have to claim it was facing “an imminent armed attack,” and therefore resorted to an act of anticipatory self-defense, arguably permitted under the UN Charter.
With its serial breaches of fundamental obligations under the UN Charter and other international laws, he says, “Russia is undermining the entire international order” and the UN itself.
Yet ironically, Russia retains tremendous power inside the UN system, as a Permanent 5 member of the Security Council, with an absolute right to veto any Council resolutions.
If Russia does send its nuclear ASAT into orbit, and the U.S. does shoot it down with a conventional missile, “You have all the makings for a large world conflict,” Beard says.
Alternatively, Russia’s detonation of a nuclear warhead in orbit, destroying rings of Allied satellites, might also trigger a superpower clash.
“Given that so many critical military assets are now located in orbit, a strong argument could be made that the next world war between the superpowers is going to begin in space, particularly in the sense that the first shot is likely to be fired there,” Professor Beard says.
Formerly a high-ranking counsel at the Pentagon, Beard is also chief editor of the globe-spanning “Woomera Manual on the International Law of Military Space Activities and Operations,” a new tour-de-force codex that focuses on the practice of states and reflects the work of vanguard space law scholars based in the U.S., Canada, Britain, Sweden, the Netherlands, France, Israel and Australia: the Manual was just released by Oxford University Publishing.
Russia’s igniting a nuclear warhead hundreds of kilometers above the Earth, or a tactical weapon on a Ukrainian city, could speedily spiral into a global conflict, says Dr. Laura Grego, research director of the Global Security Program at the Union of Concerned Scientists, and a preeminent expert on nuclear weapons, missile defense, and space security.
An initial clash of ASATs “could trigger a war between the U.S. and Russia,” she told me.
Dr. Grego says that despite Putin’s projection of power and ongoing military build-up, there are widening cracks in his facade of control that could edge him toward actually exploding a tactical bomb in Ukraine. The Russian army’s massive casualties in occupied Ukraine, and the aborted coup that briefly threatened Putin’s grasp on power, have been followed by his escalating threats on nuclear strikes.
“Russia’s activities and rhetoric indicate that it is prepared to use nuclear weapons in this conventional war in Ukraine,” she says. “It’s a very dangerous time.”
“If Russia used a nuclear weapon of any kind, and remember that most so-called “tactical” nuclear weapons are many times more powerful than those used to destroy the cities of Hiroshima and Nagasaki, Russia would become even more isolated politically and economically than it currently is,” she predicts.
“I don’t think anyone knows what happens next after the use of a nuclear weapon of any kind, but of course I’m very concerned that it risks direct conflict between nuclear-armed countries.”
Putin’s maneuvers to wage nuclear Russian roulette in the heavens or on Earth underscore the immense dangers to humanity posed by nuclear arms, says Tim Wright, Treaty Coordinator at the International Campaign to Abolish Nuclear Weapons. ICAN won the Nobel Peace Prize in 2017 for its pivotal role in promulgating the UN Treaty on the Prohibition of Nuclear Weapons.
“The war in Ukraine has awakened the global public to the very real possibility that nuclear weapons will be used again for the first time since 1945 – and the insanity of allowing any leader to have at his fingertips the means to kill on such a massive scale,” he told me.
But in an equal and opposite reaction to Putin’s doomsday threats, more nations have been joining the treaty, which calls for the absolute abolition of nuclear weapons across the face of the Earth, Wright says.
Universal adoption of the treaty, and the speedy dismantlement of nuclear warheads planet-wide, he says, would usher in a new paradisical stage of civilization, opening a spectrum of new futures for youths around the world.
