Nuclear weapons expert says we should be 'extraordinarily concerned' about Putin nuking Ukraine

• Nuclear expert Hans Kristensen said he's "extraordinarily concerned" Putin could use nukes in Ukraine.
• In an interview, Kristensen said he is alarmed by Putin's increasingly threatening rhetoric.

In a speech on Friday, an increasingly unhinged Vladimir Putin, facing battlefield setbacks abroad and growing dissent at home, railed against what he portrayed as a hypocritical and gender-mad West — his address included a transphobic rant about sex-change operations and "outright Satanism" — as he announced the formal annexation of occupied eastern Ukraine, territory he said that Russia would defend with "all the means at our disposal."

The Russian president is no stranger to colorful attacks on liberalism and, indeed, nuclear threats. Days after he ordered the Feb. 24 invasion, Putin tried to intimidate Ukraine's allies by announcing that he was putting his country's nuclear forces on a heightened state of alert and warning that those who continued supporting Ukrainian armed resistance would face "consequences they have never seen."

But that threat was almost subtle compared to those made in the months since. Earlier this week, Putin warned that Russia's potential use of nuclear weapons was "not a bluff."

Dmitry Medvedev, deputy chairman of Russia's security council and always eager to demonstrate his loyalty to Putin and his "special military operation," echoed the remarks days later, saying that Russia could use nuclear weapons in Ukraine — "without asking anyone's permission, without long consolations" — if it felt "the very existence of our state," now expanded to include the Donbas region, were threatened.

NATO would not dare respond, Medvedev added, and risk a broader nuclear conflagration over "a dying Ukraine that no one needs."

The rhetoric could be dismissed as simple tough-guy posturing from a country that's current at risk of losing a war of choice. But long-time observers are alarmed, with Russia's long-time reliance on nuclear blackmail to get its way now more explicit than ever. Putin, indeed, on Friday pointed to the United States' dropping of atomic bombs on Hiroshima and Nagasaki in World War II as "setting a precedent" for the use of nuclear arms in a conflict.

Hans Kristensen is director of the Nuclear Information Project at the Federation of American Scientists who has been monitoring Russia's nuclear rhetoric. In an interview, he spoke to Insider about signs the US and others are looking for that might point to Putin pulling the trigger on a battlefield nuke — and why his latest speech is cause for alarm. Some questions and answers have been edited for brevity.

Q. President Putin gave a speech just today marking the annexation of occupied eastern Ukraine. And in it he reiterated that he would use "all the means at our disposal" to defend Russian territory. Does that, to you, imply nuclear weapons? Did anything he say diverge from what we understand to be Russian nuclear doctrine? Anything alarming?

A. Yeah, it confirms, what he said, earlier, last week, where he was more explicit. It's his style, if you will — he likes to rattle this sword and be very dramatic, but of course, the generic term, "all means at our disposal," could also mean many other things. It remains to be seen. I think the key here is that obviously he's trying to create a new condition, in Russian declaratory nuclear policy, where just someone upsetting the integrity of Russian territory somehow, potentially, is a recipient of a nuclear attack. And that goes beyond anything that is in the current declaratory policy. That certainly requires much more significant steps here. Obviously he's trying to create a situation where there's additional coercion — pressure — on Ukraine and the West to stop fighting and seek some kind of negotiated settlement here.

Q. As you said, his rhetoric goes beyond Russian doctrine, which is, as I understand it, not so dissimilar to US doctrine: if there's an existential threat to the state, they might resort to nuclear weapons. So when you see Putin going a little bit more inflammatory, do you, as an expert, see that as just playing politics and — despite his protests that he isn't in fact bluffing — playing tough guy? Or do you think that does reflect a change in their doctrine?

A. It reflects a change in the way that the president of Russia talks about this; whether it reflects an actual change in Russia's planning for these scenarios is another matter. Frankly, I think the Russian military is probably a little less excited about throwing nuclear weapons around because they know full well what the consequences of doing that will be.

I think one could read it to sort of say this is what Putin does. This is his chest-thumping style — he likes to use big words to scare other people. But whether it's reflected in the actual planning they're doing is another matter and I think that'll take some time actually before we see that. But there are a number of steps they would have to take before they could use a tactical nuclear weapon in the Ukraine conflict. It's not like he has a red button on his desk and he could just press that when he feels like it.

Q. I'm curious if there was anything that Putin could say that you would interpret as more alarming than just rhetoric? Whether there are kind of code words that, if you saw the introduction of them into Putin's speeches, you would take that as more than just posturing.

A. Well, I thought I heard that. One of the lines in his speech was that the United States had already set a precedent for the use of nuclear weapons in war by referring to the use of nuclear weapons against Japan in World War II. I would say that's a new signal where he could begin to sort of argue, "We're not the first doing this, the Americans have already done this kind of stuff." And that could add another level of indicator that he's thinking about this in a new way.

Q. Max Seddon, the Moscow bureau chief for the Financial Times, was commenting on this speech today and he was just saying, in general, it's the most blistering attack on the West as a whole that he's ever heard from Putin. And he said that, if he were a Western policymaker wondering if Putin would really use nuclear weapons, "I'd be very concerned."

Do you share that concern or should we kind of take a step back and not get wrapped up in hysteria over nuclear weapons?

A. No, I think we should be extraordinarily concerned. And I think that concern has to translate into very deliberate efforts to convince Putin and the Russian leadership that this would take the conflict to a whole new level. We've heard some statements from US officials, of course, that they've been trying to convey that for a long time and that urgency seems to have been deepened by Putin's latest speeches and his annexation of these territories into Russia.

Q. As you probably saw, Dmitry Medvedev was basically saying that "the degenerate west" — they're not gonna want to get in a war of annihilation. That Ukraine doesn't matter, it's a failing state, if we use a tactical nuclear weapon, they're not going to risk the existence of London, Brussels, New York City over poor little Ukraine. How could the West respond to that, without laying all its cards out, to say that, "Well, no, we're not gonna tolerate that."

A. Well, Medvedev might be right about that — that the West would not want to use nuclear weapons even if Putin used a nuclear weapon in Ukraine. The point is, the use of a nuclear weapon by Russia and Ukraine is not an attack on NATO. It is not an attack on the United States. Can NATO — can the United States — decide suddenly to attack Russia with nuclear weapons if they have not been attacked first? And that's a real tough issue and I don't think that is a likely outcome.

I think the outcome is much more some intensifying of sanctions and diplomatic isolation, political isolation, maybe some cyber attacks, and in the most extreme form, probably some kind of military action. But again here, even that is hard to think about because, again, NATO has not been attacked. The United States has not been attacked. So can you start attacking Russia? That is a real hard dilemma here. So I think Medvedev, to some extent, is correct when he's saying that. Of course, the danger is that suppose Russia really thinks that it can just pop a nuke there — or several — and the West really is sort of armstrung; it can't really act, certainly not at the nuclear level.

Q. I'm certainly not chomping at the bit myself to see a war between two nuclear-armed powers. But when you talk about things like sanctions and diplomatic isolation, it's hard not to roll one's eyes and be like, okay, so essentially what you are saying is that, "Yes, they could get away with using a nuclear weapon."

A. One wildcard scenario you can imagine, of course, is that if he did do it that NATO would then — or the United States, more likely — would conduct strikes against Russian forces inside Ukraine. And that would be sort of, not quite be an attack on Russia — but of course it would be considered an attack on Russia because they are Russian forces — but it would be sort of at a half step, if you will. You could still say to the Russians, "We're doing this not to threaten Russia, as such, but to tell you that if you continue to do this then the next phase would be a lot more serious."

Q. Just to get into the more nitty gritty here, when you used the term "tactical" nuclear weapon earlier, what is the difference between a tactical nuclear weapon and a non-tactical nuke?

A. Well, tactical, or non-strategic — these are terms from the Cold War, where tactical to a large extent referred to battlefield weapons, where they were developed for wars involving nuclear weapons in a small region. Those were the type of scenarios that were very much at the center of planning during the Cold War and also because arms control treaties have looked at long-range strategic offensive forces, and never — except for the INF Treaty — looked at sort of medium- or shorter-range systems.

Today, tactical nuclear weapons are essentially anything that's not covered by the strategic arms control treaties. It tends to generally just be shorter-range systems, most of which are also dual capable: they serve both conventional and nuclear roles. They tend to be shorter range, have a wider spectrum of explosive yield options, ranging all the way from one kiloton, perhaps even less, but certainly from one kiloton to tens of kilotons even up to 100, 150, 200 kilotons in some tactical systems.

Q. When people talk about nuclear weapons, and the treaties that you're talking about that govern them, we tend to think about something that would trigger an existential war — the destruction of Earth as we know it — whereas these are to gain, to be obvious, a tactical advantage on the battlefield by hitting, say, a bunker that's deep underground. Or perhaps the reason Russia would be thinking about it is just simply the message that it would send, right?

A. Yeah, I mean all of those missions could be accomplished with strategic weapons as well. It's more about what kind of attack are you doing. What's the intensity of the attack? And here the Russians, because of their geographic position. They're surrounded by potential adversaries in their near region, right? They have the Brits, they have the French, and of course NATO forces, and then they have the Chinese. So they need, in their military planning, they need sort of regional nuclear forces, to engage those adversaries in those regions.

We could really think about them as strategic, because any use of a nuclear weapon would be strategic in nature. The "tactical" just comes in in the sense about the range of it and the intensity of the attack.

The United States does not rely on tactical nuclear weapons as much as Russia does and that's partly because the United States doesn't have regions rights next to it where it has to fight nuclear wars. It used to have more tactical nuclear weapons when it had a lot of them deployed in Europe and in South Korea, but most of those were retired and pulled out after the Cold War. It has a few hundred nuclear tactical bombs left for fighter jets, and some of them are in Europe right now, but it's not something it relies heavily on for its nuclear war planning. So the US would choose instead, if it had to respond lightly — so like a small strike in response to something — they would rely more on strategic, for example, most prominently in that scenario, strategic bombers with either gravity bombs or long-range cruise missiles.

Q. What would be the thinking behind using a tactical nuclear weapon in Ukraine? Is it kind of a situation where the worse Russia is doing on the battlefield increases the likelihood that they would use a nuclear weapon to say, "Look, just back off, NATO, stop arming this force that we're considering a proxy army against Russia"? What would be the strategic thinking — getting into the Russian mindset — of potentially using a tactical nuclear weapon in Ukraine?

A. Well, there could be several, or a combination of them. One, for example, could be to try to turn the the tide of the war — to try to knock out some Ukrainian forces or key military facilities that they need to sustain their offensive. That would be a real battlefield use, if you could say that, but that takes more than probably one weapon because you would have to hit a number of areas and a number of facilities to have a real impact on the battle, if you will. And that's also a little complicating because if you start detonating nuclear weapons in the area you potentially get radioactive fallout that you can't control — it could rain over your own troops as well, so it might not be an advantage to do that in the field.

Before the Gulf War in 1991, the Pentagon did a study on whether the use of tactical nuclear weapons against Saddam Hussein's forces there in the desert was an option. But they discovered that they would have to use a large number of tactical nuclear weapons to have a real impact — a real effect — on those forces. "Tactical" nuclear use is not as necessarily as limited and benign as some people sometimes think.

That's one option, battlefield interest. The other one is of course related, in terms of psychological effect, but it would be more sort of a more clean terror attack where they use it against, for example, Kyiv — or a couple of cities — just to break the Ukrainian will to resist. But that would also be considered a much more significant attack — much more significant use — because of the human casualties involved.

That could backfire in another way, politically, by motivating the West go in much more directly, so they really have to be careful about how they think about this. I think the big problem is with people both inside the Russian system, but also in the public in general, if they think about tactical nuclear weapons as something small; something less severe or something almost okay. That's the big danger here — that to treat that as sort of something that is doable.

Q. There's been a lot of talk of concern among US officials that Russia could potentially use nuclear weapons, and the US has been at least talking about stepping up its surveillance of Russian forces. What exactly does that mean? What are the US and its allies looking for that would signal a potential use of a tactical nuclear weapon?

A. Well, there are several steps that the Russians have to go through that they will be looking for. One has to do with the process of the decision itself. Putin would be involved in a conversation with his military leadership about this and they will have to agree. That's the most common theory about how the command decision will be made. It's not just that Putin has a red button on his desk. There are thought to be three people involved in this: Putin, the minister of defense, and the chief of the armed forces, and each of them has a vote. Presumably, if just one of them doesn't agree, then it can't happen.

But it's very iffy if that is indeed the case. We don't quite know the details of this, but even if they make a decision, that decision has to be communicated down through the command and control system to the units that have to carry it out. That traffic is potentially detectable. And then you get to the units that are then activated. So for example, before you can even fire a tactical nuclear weapons system, you have to bring the warhead for it out of central storage. So that would be activity at the bunkers — the special units that are the custodial units and the security units, they would be activated. And then they would have to either transport it by truck or fly by helicopter out to the front line to the units that would actually have to launch it. And there you would have another team that would have to install it.

So there are a number of these steps that would have to be sort of set in motion that would give away that something is happening. Whether the US is turning up its surveillance of this? I think it's been pretty busy surveilling this for a long time, actually. Satellite observations, both the visible spectrum of satellites, like normal images we can find on Google Earth, but also infrared and signal detection and then, of course, also intel. You see these spy planes that are flying along the borders all the time. They've been busy. They've been busy for a long, long time. This is a normal level of activity, I would say. And then there's spies on the ground. You have people in the system or maybe even out with some of the units that will relay information.