These are tense times in the world of nuclear deterrence. The Biden administration recently warned that Russia is considering putting a nuclear weapon into orbit, purportedly for the purpose of targeting American satellites. Two weeks later, the Department of Justice announced charges against an alleged yakuza member accused of trying to sell nuclear material originating from Iran. Against this dramatic backdrop, China is continuing to amass nuclear material, Vladimir Putin is showing off his country’s nuclear bombers, and Kim Jong Un is making noises about destroying his neighbor. To help understand all these developments, I spoke with Harvard Kennedy School professor and former White House adviser Matthew Bunn, who negotiated with the Kremlin on nuclear security as part of the Clinton administration. Bunn says that the current scenario is “by far the most intense set of nuclear dangers that have existed in my adult life.”
Let’s start with the Russian plans to put a nuclear device into orbit. Was this a contingency the U.S. and NATO have been considering for some time or more of a surprise development?
Nuclear bombs in orbit have been considered for decades. In fact, one of the James Bond movies was about a nuclear weapon in orbit. That’s one reason why they’re prohibited in the Outer Space Treaty from way back in the 1960s.
We don’t know a lot about the specifics of what the Russians may be developing. Existing weapons like intercontinental ballistic missiles can lob a nuclear bomb into low earth orbit anyway to attack satellites. So if there’s a new capability, it may be to actually put it in space permanently, or it may be a more advanced nuclear weapon designed to emphasize one particular aspect of energy release or one particular direction of energy release. For example, in the 1980s, as part of the Strategic Defense Initiative, the United States was working to develop nuclear-pumped X-ray lasers, which would force energy in a particular direction, to try to shoot down nuclear missiles. One could imagine that it might be something in that general scope, but it’s hard to speculate because we really don’t know based on the public reporting what exactly it’s about.
If Russia were to put the nuclear device into orbit, how would the U.S. respond?
Certainly there would be a huge effort to rally international opposition given that it would violate the Outer Space Treaty. And this not just a treaty like any of the others Russia has violated. This is a treaty that almost all countries in the world are party to because it makes clear that space is the common heritage of all humankind, and clearly putting a nuclear bomb up there is very much contrary to that idea. Now, Putin may not care. He has violated practically every law of war in Ukraine. He has violated the fundamental U.N. Charter by invading a foreign country and seizing chunks of its land.
But it’s a situation where one of the founding members of the United Nations, one of the permanent members of the Security Council charged with protecting international peace and security, is the one committing exactly the kind of aggression that the United Nations was founded to prevent.
How can the U.S. prepare for such a threat?
One thing the United States certainly needs to do, and has already been moving to do, is make sure that its satellite capabilities are highly resilient.
Part of that is maintaining networks of small satellites rather than relying on a few huge, expensive, difficult-to-replace satellites. Part of that is having the ability to launch new satellites to replace ones that may be harmed or disabled or destroyed. Part of that is the ability to operate without satellite support if need be. U.S. strategic bombers, for example — their pilots are trained to be able to operate without any support from satellites at all, because they’re expecting to be flying in enemy airspace with lots of electronic jamming and so on. The guidance systems of U.S. long-range nuclear missiles don’t depend on any communication from the outside world or from satellites because of the concerns about electronic interference with such communication. But for a lot of the U.S. military, space is fundamental to their operations. Still, there are opportunities for at least temporary alternatives in the way of ship-to-ship, air-to-air, ground-to-ground communications, et cetera.
This is just one nuclear threat among many right now. Russia has warned of using nukes on Ukraine over the past two years; how do you view that possibility at the moment?
This is part of a broader collapse of U.S.-Russian relations and a broader Russian decision to try to highlight its nuclear threats to the West. Putin and other people in his government have repeatedly issued such threats since they invaded Ukraine two years ago. Most recently, just a few days ago, Dmitry Medvedev, who had been president of Russia and is now deputy chairman of the Security Council, said on his Telegram channel that if Russia was pushed back to its internationally recognized borders, it would launch all-out nuclear war, including the destruction of Washington, Paris, London, and Berlin. And as far as I’m aware, virtually no western newspapers even bothered to report that because so many Russian nuclear threats have already been made.
Among Russian nuclear strategists, there is a sort of public discussion about “How do we get the West to pay more attention to our nuclear threats?” And one could easily imagine that moving toward a nuclear weapon in space would be one aspect of that.
It’s a really dark situation in nuclear relations between the United States and Russia. Almost all nuclear-arms agreements limiting U.S. and Russian forces are gone. Only the New START Treaty remains, which is still in force, although Russia is violating its provisions by refusing to allow inspections. Both sides have said they will at least remain within the numerical limits of that treaty for the time being. But that treaty expires in February 2026, and there are absolutely no talks underway to consider any sort of replacement. So it may be that quite soon, for the first time in half a century, we’ll be in a world with absolutely no limits on U.S. nuclear forces or Russian nuclear forces. There already have never been any limits on Chinese nuclear forces, which are now getting built up, and relations between the United States and Russia are more hostile than they have been since the Cuban Missile Crisis.
Where would you place the current threat level compared to the Cold War era?
This is by far the most intense set of nuclear dangers that have existed in my adult life, and I’m in my 60s. I gave a talk a little while ago summarizing nuclear dangers around the world generally, titled “The Darkening Horizon.” It’s not just U.S.-Russia, but U.S.-China, U.S.-North Korea, India-Pakistan, Iran, et cetera. It’s bad, and our efforts to try to moderate the danger are just not working very well. Russia is refusing any serious talks on nuclear issues. North Korea is refusing any serious talks on nuclear issues. To the Biden administration’s credit, they’ve managed to get some conversations with China going again, but at a very limited level, which so far is not affecting the rapid Chinese nuclear buildup underway. India and Pakistan continue nuclear-arms competition more or less in slow motion. I’d say just “arms competition,” but you have incidents like India accidentally firing a cruise missile in the middle of Pakistan — a nuclear-armed country whose government is very much up in the air at the moment.
What do you take away from the Justice Department’s announcement last week that the FBI had arrested an alleged yakuza member accused of selling nuclear material obtained from an insurgent group in Myanmar? That also sounds like a spy-movie plot.
It’s a reminder that there may well be potential nuclear-bomb material out of the control of any particular country. We also don’t know how important this particular episode was because we don’t know how much nuclear material the smuggler had and how much more that smuggler might have access to. But it apparently was weapon-grade plutonium, and the undercover agents who caught the smuggler told him that it would go to an Iranian nuclear-weapons program. So the smuggler was not at all concerned about the possibility that they were supporting the spread of nuclear weapons.
For decades, the United States has been worried about the possibility that terrorists would get hold of the essential ingredients of nuclear bombs and has tried both to help countries improve their security and account for nuclear material. Stopping nuclear smuggling is a really hard problem, because the amount of material you need for a nuclear bomb easily fits in a suitcase. And while it’s radioactive, it’s not that radioactive. I mean, you can carry it around. I’m fond of using a photograph from the Manhattan Project of a man who is wearing a T-shirt and remarkably dirty chinos and he has a box that he’s holding in one hand and the box has it at the plutonium for the first-ever nuclear bomb for the Trinity test. And it’s just an example that this stuff is not hard to carry around and it’s really hard to find once it’s out of the place where it’s supposed to be.
What did you take away from the pictures in the indictment, which prosecutors describe as showing small amounts of nuclear material?
There clearly was nuclear material there. It clearly was small quantities of nuclear material. Some of it appears to have been what’s referred to as yellowcake.
The indictment says there was uranium, there was thorium, and there was plutonium. Plutonium is the only one where they mentioned the isotopic content and say that it was weapon grade. But we don’t know how much — and it might’ve been just contaminated with plutonium or some very small amount of plutonium.
But one mystery about the whole thing is that it was being smuggled from Myanmar, which does not have a nuclear program. There have been suspicions over the years that they might be starting a nuclear program, but there’s no evidence they actually have any plutonium or any substantial amounts of uranium that would be a serious problem. Myanmar’s dictatorship does have decently close connections to North Korea. And North Korea, of course, has a lot of plutonium and a lot of enriched uranium. There are sanctions that bust operations from North Korea, which ships nuclear material to places like Myanmar, which then ships it somewhere else. And it’s certainly true that the North Korean government makes use of crime groups to help get what it wants. There’s absolutely no evidence in the indictment that there’s any such connection, but I’m just speculating as to why on earth something coming from Myanmar would be nuclear.
We’ve talked a lot about recent escalations of the nuclear threat. How can the U.S. deescalate in this uncertain time?
One of the key lessons that President Kennedy drew from the Cuban Missile Crisis was to always give your adversary a face-saving choice between humiliating defeat and nuclear war. And unfortunately, I think we have to be thinking that way. What is a climb-down option for Putin in the Ukraine war? At the same time, Putin does not appear to be looking for a way out at the moment. He appears to be looking to dominate Ukraine indefinitely.
This interview has been edited for length and clarity.