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The world rejected sham referendums Russia used to justify annexing four Ukrainian regions, and its military has been beaten back from key parts of the areas.
But Russia now views the areas as “inalienable parts of the Russian Federation,” Kremlin spokesman Dmitry Peskov told reporters Tuesday.
Paired with Russian President Vladimir Putin’s suggestion last month that Russia is ready to use its nuclear arsenal to protect its territory, it seems Russia now believes the sphere protected by its nuclear weapons includes these parts of Ukraine.
Back when Russia invaded Ukraine in February, the Texas A&M University professor Matthew Fuhrmann told me the likelihood of Putin actually using a nuclear weapon was low. Along with Todd Sechser, Fuhrmann wrote the 2017 book, “Nuclear Weapons and Coercive Diplomacy.”
I called Fuhrmann to ask if this new rhetoric has changed things, if Putin is rational and to get a better sense of what we know about the so-called tactical nuclear weapons Russia could theoretically use. Our conversation, edited for length, is below.
What has changed since the war began?
WOLF: How have the last six months changed your impression of the worldwide nuclear threat?
FUHRMANN: Certainly in the last few weeks and months, we’ve seen Russia continuing to try and play the nuclear card as a way to gain leverage over the West and especially the United States. The continued insertion of nuclear threats into the crisis has made me and others think more about the possibility of nuclear escalation.
On top of that, we’ve seen Russia resort to other policies, like conscripting additional forces and openly targeting civilians in Ukraine, that raise questions about other things it might be willing to do down the road should things escalate further. So we’re in an environment now where a lot of people are very much thinking about the nuclear dimension here.
Biden thinks Putin is ‘rational.’ Using a nuke would be irrational
WOLF: President Joe Biden recently described Putin as a “rational actor” who miscalculated, but I think there’s something irrational about even threatening the use of nuclear weapons. What did you make of what Biden said? And do you think that Putin right now is acting rationally?
FUHRMANN: I do think he’s a rational actor. A rational actor just means you’re making decisions based on a calculation of costs and benefits.
So someone can be rational and make decisions that we think are risky or problematic. But as long as they’re making those decisions on the basis of some means and calculation, factoring in costs and benefits, then I would still characterize them as a rational actor.
How could Putin possibly benefit from a nuclear strike?
WOLF: There’s been a lot of skepticism that Putin would actually cross the line and use some kind of nuclear weapon. He would need to frame it as a defensive measure or as a response to a strike on the Russian homeland. Is there anything specifically with regard to that idea of a cost/benefit analysis that suggests it would be worth it for him to use nuclear weapons?
FUHRMANN: I think the probability of Russia using nuclear weapons right now is still relatively low. I might put it slightly higher than I would have in late February, when the when the conflict was first picking up, but I still think it’s relatively low.
The reason is that you have to think about what Putin would gain from using nuclear weapons as well as what the cost would be. And the costs are potentially enormous.
What we’re probably talking about here would be the use of a tactical nuclear weapon – something with a lower yield, that will result in fewer casualties, less radioactive contamination compared to a larger strategic weapon.
Even still, the cost will be tremendous. And the benefits of doing so for Putin are also not totally clear.
If he wants to occupy Ukraine, it doesn’t make much sense to destroy territory that he wants to claim for Russia.
The likelihood he would do so is still relatively low, but it’s not zero.
A nuclear message
WOLF: What are potential scenarios?
FUHRMANN: More than using a nuclear weapon on the battlefield, what he might be more likely to do would be some kind of nuclear detonation in the middle of nowhere as a signal to tell the United States and the West, hey, back off. If there was going to be nuclear weapon use, that’s the scenario where I think it would be most likely based on the way things have gone so far.
Tactical vs. strategic
WOLF: You just made a distinction between a tactical nuclear weapon and a strategic nuclear weapon. It seems like you’re crossing a line no matter what kind of nuclear weapon you use.
FURHMANN: You’re definitely crossing a line no matter what kind of nuclear weapon you use. That’s true.
But it’s also true that there’s huge variation in terms of the kinds of nuclear weapons and the damage that they can inflict, and I think that that variation is important.
A larger strategic warhead like the ones the United States uses on intercontinental ballistic missiles – if it’s detonated in a big city – that can kill 100,000 people or more. That is different than a smaller tactical nuclear weapon that if it was targeted in a populated area could kill maybe a few thousand.
Both events would, of course, be terrible and catastrophic. But I think there is a distinction between those two kinds of things.
How would a tactical nuclear weapon ruin the environment?
WOLF: What would be the lasting environmental effect of even a tactical nuclear weapon? How long before people could go back and live in an area where one was used?
FUHRMANN: That would depend on a lot of factors. It would depend on the size of the warhead. It would depend on how far above the ground it was detonated.
If it was detonated right at ground level, that means something different than if it’s detonated a mile in the air. It would also depend on things like wind patterns.
So it’s difficult to make a blanket statement about what the effects would be. In general, yes, you would have to worry about the radioactive contamination of an area anytime a nuclear weapon was used. How bad it would be would be a function of those variables.
What do we know about Russia’s tactical nuclear stockpile?
WOLF: It’s my understanding that some tactical nuclear weapons can be very small and essentially deployed by an individual soldier.
FUHRMANN: We don’t know nearly as much about Russia’s tactical nuclear forces and what they have as we do about Russia’s strategic nuclear weapons.
That’s in part because a lot of the prominent arms control treaties that were concluded between the United States and Russia dealt with strategic nuclear weapons. Through those negotiations and treaties, we learned something about the stockpiles that each country possesses as far as strategic warheads go.
But there’s been no comparable bilateral arms control dealing with tactical nuclear weapons. They do likely possess a range of different tactical nuclear weapons with different capabilities. It depends on the command and control procedures that are in place, but tactical nuclear weapons in general are much more portable than a strategic nuclear weapon. They’re designed for use on the battlefield and so they can be fired by a single soldier.
What are the signs Putin would be gearing up to use a nuclear weapon?
WOLF: What would be a tell that Russians were going to get ready to use one of these? Would they fortify themselves in a specific way or clear out of an area?
FUHRMANN: Tactical nuclear weapons, to my knowledge, are not presently deployed. If Russia was going to do this, it would probably want to do it in a way that was visible to the United States through satellite imagery and other means.
You could see, for example, weapons moving out of storage, and weapons moving to the frontlines. These are things that would be observable, in theory, by US satellites. And to my knowledge, we haven’t seen any of that happening yet.
Why don’t treaties cover tactical nuclear weapons?
WOLF: It seems strange, that we kind of dealt with the mutually assured destruction weapons (strategic nuclear weapons), but then there’s this whole subgroup (tactical nuclear weapons) that’s floating out there that countries don’t have a lot of knowledge about.
FUHRMANN: The emphasis was on the strategic weapons because these were the big weapons that could destroy cities. I think it was natural to focus attention on those as being potentially the most destructive and therefore the biggest threat.
But yes, tactical nuclear weapons are still very significant. And it would be useful to think about arms control in that context as well.
What is the US stockpile of tactical nuclear weapons?
WOLF: Does the US still maintain tactical nuclear weapons? And what should people know about the American stockpile?
FUHRMANN: During the Cold War, the United States had a fairly large stockpile of tactical nuclear weapons. … It was believed that the only way to defend NATO in Europe from a Soviet attack was to have tactical nuclear weapons deployed that could be used, should Soviet troops try to advance into Western Europe.
When the Cold War ended and the Soviet threat was dissipated, most of these weapons were dismantled or returned home. There are still some US tactical nuclear weapons in Europe. Not many. And they’re weapons that are militarily not all that useful. Compared to Russia, the United States has at this point, fewer tactical nuclear weapons.
Will the US now reconsider its own tactical nuclear arsenal?
WOLF: Will this current situation lead the US and NATO to rethink whether they should have more access to tactical nuclear weapons?
FUHRMANN: I think probably some people in Washington are already thinking that the United States should be more equipped with a greater number of smaller-yield tactical weapons.
Even before Russia invaded Ukraine, there were debates in Washington about whether the US should develop lower-yield weapons. It was feared that if Russia used one of the lower-yield tactical nuclear weapons that it possesses, the United States doesn’t have anything comparable. So if it were going to retaliate, in a nuclear sense, it would have to use a bigger nuclear weapon, which could be seen as an asymmetric response.
There were some generally more hawkish commentators and policy analysts who, even before the Ukraine war, were pushing the United States to develop these lower-yield nuclear weapons. And ironically those arguments will gain weight if Russia continues to make nuclear threats.
Should Russia’s posturing lead to an increase in the US arsenal?
WOLF: Do you have a position on that? What do you think should happen?
FUHRMANN: My feeling is that nuclear weapons are useful as invasion insurance and as a deterrent against very major threats to national security. I don’t see them as terribly useful for blackmail or for other forms of political coercion.
With that view, the reason you would need a tactical nuclear weapon, low-yield, would be for battlefield use. I think that that opens a really dangerous precedent to start thinking about weapons that you’re going to use on the battlefield.
I think about nuclear weapons as a weapon of last resort that you would use to stave off an invasion or full occupation of your territory, not something you’re going to use on a battlefield in a nonexistential type situation.
Are these stockpiles secure?
WOLF: I remember after 9/11, there was a lot of concern that the Russian stockpile in particular could be infiltrated or that we could see one of these tactical weapons used as a dirty bomb. Has that threat receded, or are we just not paying attention to it right now?
FUHRMANN: In general, one problem with tactical nuclear weapons is that it is harder to secure them because they’re smaller. We know that there were some tense moments and in the US history with nuclear weapons in terms of worrying about its tactical forces falling into the wrong hands. Anytime there’s a lot of political instability in an area where nuclear weapons are stored, there are always concerns about them potentially falling into the wrong hands.
In the United States there are security measures in place and safety measures that make it more difficult to use a nuclear weapon.
What exactly Russia has as far as those safety and security procedures in place, I’m not sure. But one would hope that they have something along the lines of what the United States has in that regard. That could make it more difficult for someone who can actually fire any tactical nuclear weapon, even if they could hypothetically get their hands on it.
The US can have an effect on the threat from Putin
WOLF: What else should we know?
FUHRMANN: A lot of people understandably want to know: Are nuclear weapons going to be used or could they be used by Putin in this conflict?
The United States, through its actions, influences that probability to a large degree. To the extent that the United States were to escalate its military involvement in the war, do anything to strike targets in Russia itself, do anything to put troops on the ground in an overt way and actually enter the conflict, all of those things would significantly increase the risk of nuclear escalation.
How should the US help Ukraine without tempting nuclear war?
WOLF: At the same time, you’re starting to hear more and more lawmakers, in particular Republicans, questioning military aid to Ukraine at all. What is the right way to strike that balance?
FUHRMANN: It’s a great question, and there’s no silver bullet answer, but you can look at history to get some guidance.
Throughout the Cold War, there were many episodes where nuclear powers were indirectly involved in conflict with each other. You can think, for example, about the Soviet Union and their invasion of Afghanistan in 1979. And the war that persisted there over the next 10 years.
The United States was covertly providing a lot of support to the mujahedeen fighting against the Soviets. Not unlike the aid that has been provided to Ukraine now. The Soviet Union was, for its part, doing things to provide aid in the Korean War.
There’s a long history of nuclear powers indirectly fighting one another by providing aid to the country militarily engaged with a nuclear power. In none of those cases, so far, did it escalate to the nuclear level.
That doesn’t mean it couldn’t happen again in the future, but I think there is a line that countries have been willing to walk up to – and that line appears to be providing covert support quietly to actors engaged in conflict with other nuclear powers but not openly entering the fray.