Retired U.S. Brigadier General Kevin Ryan is a senior fellow at Harvard Kennedy School's Belfer Center for Science and International Affairs and a regular commentator on the war in Ukraine and other global events.
He talked to RFE/RL's Georgian Service about who and why either side would have destroyed the Nova Kakhovka dam, how it could affect a Ukrainian counteroffensive or other battlefield plans, and perceived Western failures in deterrence against Russian President Vladimir Putin's possible use of a nuclear weapon.
He argues that Putin could resort to nuclear weapons rather than lose Russian forces' land bridge in southern Ukraine, occupied provinces, or annexed Crimea.
RFE/RL: The Nova Kakhovka dam is no more, essentially. For some, there are still questions as to who might have done it, despite everything pointing to Russia. In whose interest would it be to blow it up?
Kevin Ryan: It's in neither side's interest to blow up the dam at this moment. I've heard three different kinds of reports. I've heard reports that say, "Russia has done this." Those reports come mostly from Ukraine and from the West, they come from the U.S. government and from NATO. They may have evidence of that.
Retired U.S. Brigadier General Kevin Ryan
The Russians, of course, claim the Ukrainians have done this. There's a third group of reports -- they're small but they're important -- and those were given both by the Russian news agency TASS and by a local Russian governor who said that "actually, there was an accident on the bridge prior to this [and] that accident has led to an unexpected and undesired," let's say, "break in the dam."
At this moment, all three are possible.
It doesn't really benefit Ukraine to have this happen. It doesn't benefit Russia, either; although if Russia did break the dam and blow it up, what it reveals to me about Russia and Russian military leaders is that they have very little confidence in their defenses of the Kherson region -- defenses which they've been building steadily since the summer and are extensive.
If I were them, I would not have flooded this area -- yet -- until I saw that, No. 1, the attacks were coming in this area and, No. 2, that my defenses were not going to be able to hold that attack.
RFE/RL: So it was an act of desperation?
Ryan: It would seem to be an act of desperation, if it was the Russians who did it.
RFE/RL: How does this translate onto the battlefield, from a tactical perspective? How is it going to affect any Ukrainian counteroffensive?
Ryan: The flooding is significant, especially to the southern and eastern side of the waterway [Dnieper River], and this will make it impossible to cross the river for a large military force -- say, Ukrainian -- for the immediate future; let's say for the next week or so. Then after that, the river could be crossed again, but the terrain would be muddy; there would be areas of the terrain where we didn't understand the damage until we get there, so it complicates any maneuver in that region [or] any plans that were made there. That's the near-term effect.
The long-term effect is all the damage to water usage, hydroelectric power, and so on, not to mention the crops and foodstuffs that would have been coming from this region.
The Tavberidze Interviews
Since the beginning of Russia's full-scale invasion of Ukraine in February 2022, Vazha Tavberidze of RFE/RL's Georgian Service has been interviewing diplomats, military experts, and academics who hold a wide spectrum of opinions about the war's course, causes, and effects. To read all of his interviews, click here.
RFE/RL: What you just mentioned has also been put forward as yet another argument why Russians would be behind this: Strategically, the most direct route to move to the border of Crimea basically has been cut off; Ukrainians can no longer attack in the Kherson direction unless they mount a highly unlikely amphibian assault. What this means is that the front line has been narrowed and shortened and Russia has the luxury of using their forces there to reinforce the eastern flank. Is that a correct line of reasoning?
Ryan: Yes. I laid out three possible scenarios for how this could have happened: Ukraine, accident, or the Russians. But I didn't say which I think is the most likely; and I'd agree that it is the Russians who did that because they are the ones who will benefit the most tactically and operationally from that flooding.
RFE/RL: On the other hand, the Russian positions on the riverbank seem to be washed away as well. Would you agree that it's unlikely they'll be able to salvage much of the equipment they had there?
Ryan: I don't know about the damage to Russian defenses. Yes, any defenses that were in a flood zone would be washed away or broken up, and this makes it unlikely that those defenses can operate as they were planned.
Certainly the troops will have had to leave those defenses, which makes them very vulnerable to an attack. But the [Russian] defenses within the Kherson province have been built in-depth, and they go all the way back to the isthmus for Crimea and to the north to Zaporizhzhya. There are plenty of defensive lines left outside the floodplain which will still be standing and which will have soldiers in them.
RFE/RL: Whether or not Russia did it, it will impede the Ukrainian counteroffensive and buy the Russians time. Would that be a fair assessment?
Ryan: Absolutely. From the Ukrainian side, the flooding has to delay any major operation or movement in that region. It may be that Ukraine had foreseen the flooding and the breaking of the dam, and maybe they hadn't planned for their major offensive to be in that area. But whatever was planned will be delayed, at the very least, and slowed down.
RFE/RL: Some claim Russia has shot itself in the foot by depriving the north of Crimea water supply from the Nova Karkhovka dam "for decades." Others claim it's not likely to have any significant effect as Crimea was also supplied from Russia for the past eight years, between the 2014 annexation and last year's full-scale invasion.
Ryan: The destruction of the dam creates a more serious problem than existed when Ukraine owned the territory and had simply cut off the canal to deprive Crimea of freshwater.
The Russians coped with that over the years, so we know that the Russians are able to cope without the water from the north and they will likely do so for a while. But the destruction of the dam makes restarting that waterflow a much more difficult problem even if the war ended today.
This will take a long time for Russia to regain water from the north, the major source of water into the region, and this will have an impact not only on the people and the civilian communities but also on the military and its operations out of the Crimean Peninsula.
SEE ALSO: A Quick Ukrainian Defeat Of Russia Lessens Chances Of 'Black Swan Event,' Argues Former Military Adviser To UkraineRFE/RL: If Russia is able to supply Crimea from other sources, does it not make sense to take this leverage out of Ukrainian hands?
Ryan: Absolutely one of the reasons why Russia established the land bridge that it has established and fought this war was to control the access to Crimea and to ensure not only electrical power, energy supplies into Crimea, but the water supplies.
Russia has that at the top of their list of things to do for Crimea and to protect as a result of this war that they've started. If Ukraine is able to take those things away from Russia, that will be an intolerable situation in the mind of [Russian] President [Vladimir] Putin and the military, and would be one of the triggers which cause him to escalate the violence in Ukraine by any means possible, as he has said many times before -- alluding to the fact that they have nuclear weapons.
RFE/RL: How concerned should be we about the Zaporizhzhya Nuclear Power Plant? There have been alarming reports of a shortage of "coolant water" that was previously supplied by the Nova Kakhovka dam.
Ryan: The Zaporizhzhya energy station, which is all nuclear, is an important factor in this war and back and forth, whether or not we're talking about the Kakhovka dam or not. Even before the Kakhovka incident, there was fighting around that energy station and damage to it could have led to a nuclear meltdown along the lines of Chernobyl, only bigger, because, remember, this station is much bigger than Chernobyl.
It's very much a possible weapon that Russia could use against Ukraine by creating a nuclear accident there that not only irradiates the local area but threatens people downwind from any nuclear meltdown.
Remember, after Chernobyl many people throughout Europe claimed, and in some cases were shown to have developed, cancers from the fallout from that nuclear meltdown, radiation. So this could happen again but only two or three times bigger in regard to this nuclear station.
Ukrainian emergency workers wearing radiation protection suits attend training in at the Zaporizhzhya nuclear plant, which largely relies on water from the now-emptying reservoir at the Nova Kakhovka dam.
RFE/RL: Could this Nova Kakhovka incident be a sort of a testing ground for Russia, if they see this puts Ukraine on the backfoot, if Ukrainian forces and people are in disarray, if they see it's effective? Could that prompt Russia and Putin into going one step further and doing something with Zaporizhzhya?
Ryan: I don't see the two as a sequential kind of stepping-stone situation. Yes, if Russia were to create a nuclear incident in Zaporizhzhya and to gain some advantage from that to put the Ukrainian government in disarray or tied up [Ukrainian] forces trying to save people in the region, that would all benefit Russia to a large degree. But it doesn't destroy the Ukrainian military; it doesn't prevent a Ukrainian offensive ultimately elsewhere in the country, or just after the accident is contained.
The use of a nuclear weapon by President Putin would happen if he was going to lose the land bridge or the provinces that he's taken or if he was going to lose Crimea, and that could happen irrespective of what's going on in Zaporizhzhya.
RFE/RL: If the argument is that Putin will resort to tactical nuclear strikes if he sees that the land bridge is in danger, does he view [possible] leakage or contamination at the Zaporizhzhya plant as a similarly effective weapon at this disposal?
Ryan: No, I don't think that President Putin or the Russian military leaders see a nuclear accident or the radiation produced from that in the same way that they see the mushroom cloud of a nuclear strike. That mushroom cloud represents not only horrible death and damage and harm to Ukrainian people, but it also represents the power of a nuclear superpower and the ability of that superpower to deliver Hiroshima- and Nagasaki-type weapons. That's a different kind of message or…projection of power.
RFE/RL: In a recent essay, you argued that Putin will indeed resort to the use of nukes to avert defeat in Ukraine. An overwhelming majority of Western experts and analysts have been saying this is an unlikely scenario. You don't seem to share that optimism. Why?
Ryan: I'm not the first to warn his threats are serious. Many people say that his threats are serious, but then they quickly say, "However, they are not likely." But this undermines the first part of the sentence. Why would you take a threat seriously if it's not likely to happen?
I'm one of the few people who has said that these threats are not only serious but they're likely to happen. That makes a threat urgent -- something which others are not saying. If these threats are recognized as urgent, then the governments will do something about it; if they're not urgent, or if they're not likely, then the governments have many other things on their plate that they want to take care of that are urgent.
Russia launches a Sarmat intercontinental ballistic missile from Plesetsk, northwest Russia, on April 20, 2022.
I'm not an alarmist, although people may want to call me one because of what I've said and written. But my intent is not to alarm civilians. For the people living in that region -- Ukrainians and Russians alike -- this is not a theoretical discussion.
Instead, my audience are the political leaders in Moscow, Washington, Kyiv, and NATO capitals. They underestimate the likelihood that Putin will follow through on his threats to use nuclear weapons. When they underestimate that, when they consider these threats unlikely, they push aside the question of what to do about it.
We don't have that luxury anymore. We must think ahead and think now about what to do for medical preparedness, the humanitarian-aid preparedness, military preparedness to operate on a nuclear battlefield. All these things -- we need to be doing more about that.
RFE/RL: So you're not buying the argument that Putin has been categorically convinced not to use nuclear weapons in Ukraine, that there would be catastrophic consequences for that, if you take Victoria Nuland's quote, for example?
Ryan: I don't know that anything we say or do in the West would ultimately cause Putin to either use a nuclear weapon or not use a nuclear weapon. This is his decision. He has shown that he's making decisions about this without the support of many world leaders [or] even people within his own military and government.
He's had to silence a lot of people who spoke out against that…. Because Putin is making his decision based on his own situation and on the situation of the Donbas regions, Zaporizhzhya, what they have taken there, he will use the nuclear weapon if he cannot escalate conventionally to prevent the loss of those things.
I don't think that the West has really offered him or shown him anything that would deter him from using a nuclear weapon in Ukraine. Is it economic sanctions? Those have not stopped what he's done so far. Is it a catastrophic military strike? The West could possibly do that, but they're not prepared to do that. They have not marshaled their forces and moved them to within the borders and so on to create the strike. And the United States government has said flat out that it will not attack Russian soldiers and start World War III.
RFE/RL: The United States has said it won't reciprocate with a nuclear strike, but not that it wouldn't attack Russian soldiers or Russian planes. There was even an implicit threat that the West might sink the Russian Black Sea naval base, for example.
Ryan: In this point, I have to disagree with you. [U.S.] President [Joe] Biden has said on TV that he would not have a situation where American soldiers are killing Russian soldiers. He said that would equal a third world war. The comments that you are quoting, about destruction of the Black Sea Fleet, came from other people, too, but most recently from General [David] Petraeus. He's not a representative of the government, and he doesn't speak for the government. And he would be the first person to tell you that.
While that could be an example of a catastrophic response, I think it has been taken off the table by the United States. I don't know about other NATO countries -- NATO countries are supposed to act in concert, but they can act independently. There could be a NATO country which decides that they wanted to follow the advice of those who say we should bomb the Black Sea Fleet. But I don't think that's in the cards; I think we've removed that from the possible responses.
RFE/RL: What kind of deterrent does the West have at hand to make sure [a nuclear attack] doesn't happen?
Ryan: We don't have the ability to stop Putin from doing this, because we have said we will not respond with a nuclear weapon, and I believe we have said we will not respond with a massive conventional strike.
The word "catastrophic" has been used, but I don't know what that could be -- it must be catastrophic in terms of economic and diplomatic, and informational domains, because it certainly is not catastrophic in terms of military domain.
Frankly, I don't think there's anything that the West can do to stop President Putin from using a tactical nuclear weapon in Ukraine if he chooses to do so.
What we could do as a result of that, there are many things. We could then change our position and say, "OK, you have used a nuclear weapon now, and so, from here on out, we are going to do the following things if you use another nuclear weapon." We could say, "Well, we will enter the war" or "We will do what some have suggested, and we will strike the Black Sea Fleet or other things."
RFE/RL: Why not say that now?
Ryan: That's a great question. Today, how we see this war and the situation there -- the balance of forces between the Russians and the Ukrainians, the West and so on -- is much different than we saw it in the lead-up to this war or in the first few days of the war.
Our positions and policies have evolved over the time of this war. That's to be expected. I don't think there's any shame in that. Both sides were unprepared for the intensity of this war and unprepared, frankly, for the success that the Ukrainian people have had and the stamina that they've had in this war -- and the lack of that on the Russian side.
All of these things mean that what we would say today is certainly different than what we would have said a year ago. In that regard, I think we could come out and change what we're saying to Russia if we thought that it would affect their possible use of a nuclear weapons.
Graves of unidentified people killed by Russian soldiers during the occupation of Bucha, Ukraine, are seen at the town's cemetery on March 30.
RFE/RL: The reality and narrative need to be shaped for that. In other words, does a "nuclear Bucha" need to happen for the West to change its approach? (Editor's note: Bucha is the city outside Kyiv where a pullback by Russian occupation forces entailed what Ukraine, many Western governments, and international rights watchdogs have alleged are widespread war crimes against civilians.)
Ryan: I hadn't considered that analogy, but that's a good one. A "nuclear Bucha" is precisely what President Putin would be going for if he were to use a nuclear strike in Ukraine. He would be trying to terrorize both the Ukrainians and the West and to get people to stop the war, have a cease-fire, which would leave him -- if it's done early now -- with most of what he needs and wants.
[Russian Defense] Minister [Sergei] Shoigu has said that Russia has accomplished most of its goals. [Yevgeny] Prigozhin, the bombastic leader of the private military company Wagner, says Russia has accomplished most of what it needs and wants. I think that Putin feels that he's accomplished a lot and he could sell this as a victory. But at the moment, he can't stop fighting, because the Ukrainians are not stopping.
RFE/RL: Let's take this scenario where he does opt indeed for using the tactical nuclear strike. You write: "In today's situation, a single nuclear strike in Ukraine could thwart a Ukrainian counterattack with little loss of Russian lives." So, the big question would be, how would it happen? And where?
Ryan: There are different targets that the [Russian] military and General Staff could be considering in Moscow as they prepare for that plan, if they were called on to execute it. They could choose civilian populations and create the most terror and damage to the Ukrainian people…like Hiroshima- or Nagasaki-type situations. They could choose military formations to bomb.
Once the main thrust of the offensive is known and visible to everybody, then Russia could attack the center of those forces with a nuclear strike and destroy as many forces as they could. That is what I meant in my article by saying that they could thwart that offensive.
But I want to point out that during the Cold War both Russia -- the Soviet Union --- and the West -- the United States -- trained for these kinds of battles. We trained to operate on what you call a nuclear battlefield, where one side or the other has exploded a nuclear weapon and yet the forces still need to continue fighting. They decontaminate, they reform, they reassemble, and then they fight in a more dispersed kind of formation, but they continue to fight. Thankfully, this never happened in our lifetime up to now.
If Putin were to explode this nuclear weapon, that would happen for the first time in history: You would have Ukrainian forces which would not stop fighting; they would continue to fight. But they would need to fight on a battlefield where a nuclear weapon has been exploded and might be exploded again. Then you have radiation problems, you have all sorts of additional problems.
RFE/RL: That's postapocalyptic.
Ryan: It is. It is a horrible situation which we cannot overstate the seriousness of, if it happens. This goes back to my article, where I think that it's so hard to envision this, so hard to think about it, that it's easier to say that it is not likely and then therefore we don't really have to spend a lot of time on it.
RFE/RL: If the nuclear strike were to happen and the Ukrainians continued fighting, what would Putin do then? Use more nuclear strikes?
Ryan: In a case where Ukraine continued fighting, I think he would feel free to use additional nuclear strikes if he thought that that would be the most efficient and helpful way of destroying Ukrainian forces or forcing Ukraine to stop fighting.
RFE/RL: And if he'll be allowed to by the rest of the world?
Ryan: I don't think the rest of the world is really controlling what Putin does. Even China, who many people say, well, China has, quote, unquote, told Putin not to use a nuclear weapon, that this is the red line for them. China told Putin that they didn't want an invasion of Ukraine. And Chinese leader Xi Jinping and his leadership have been talking about the fact that we need to turn down the rhetoric about nuclear strikes, and nuclear weapons, and nuclear threats.
They've been saying that out loud -- for Putin to hear -- for months, and yet those threats continue. Yes, Putin and Russia need China and they need that partnership, but again, I don't think Putin is motivated ultimately by that consideration if the alternative is losing this war or losing [the] Zaporizhzhya and Kherson provinces, or losing Crimea. He, in those cases, would not hesitate to do whatever he needs to do.
RFE/RL: The final question will be me trying to spot some silver lining. You envisage a scenario where Putin faces a defeat on the battlefield and losing Crimea, and he orders a tactical nuclear strike because its his reign and his life at stake, right? But is the order carried out, necessarily? What are the chances that he will be told, "It's your head on the line, not ours, and not Russia's"? Can he risk that?
Ryan: Putin would risk such a situation. But your suggestion of what would happen if he did give such an order is a good question. It is always possible, especially in the Russian system, that somebody could interrupt that order -- either at the Putin level and his inner circle or at the level of Shoigu, [General Valery] Gerasimov, and the two generals who would have to carry it out, Generals Oleg Salyukov (who is in charge of ground forces) and [Sergei] Surovikin (who is in charge of Russia's invasion forces in Ukraine).
It's possible that they could decide that "this is too far, and we must stop it." But it's not likely that they would stop it. They have been hand-selected since January to lead this operation. In January, Putin put the three generals who run his tactical nuclear forces in charge of this operation. They are the most loyal. Their reputations, their careers, their lives depend on following his orders.