INDIANAPOLIS –  U.S. Sen. Sam Nunn was at a conference in Hungary when a coup d’etat toppled Soviet Leader Mikhail Gorbachev in the summer of 1991. A Soviet contact called him. “You’ve got to get over here,” Nunn was told. “Big things are happening; great opportunities and huge dangers.”

Once in Moscow, Nunn would spend half a day milling around the Russian White House where Boris Yeltsin had made his stand. In the Duma, Nunn sat for two days in the gallery and watched the debate which would bring about the collapse of the Soviet Union, a stunning turn of events that, literally, no one saw coming.

“I combined that with having been so involved with the Vietnam War and knowing what happened when a country lost a war,” Nunn explained to Howey Politics Indiana during a 2007 interview in Yekaterinburg during a codel with Sen. Richard Lugar. “I saw that Russia was unraveling and multiplied it by a hundred because we lost one conflict that was devastating to our psyche and military.”

Today, Nunn is co-chair of the Nuclear Threat Initiative, a private organization working to reduce nuclear and biological threats. He partnered with the late Sen. Richard Lugar to create the Nunn-Lugar Cooperative Threat Reduction Program, which would eventually secure and eliminate thousands of Russian nuclear, chemical and biological weapons at a cost of less than $20 billion. Lugar told me in 2007, “We had spent $6 trillion trying to contain the Soviet Union and now it’s all going to come loose.”

On Monday, HPI interviewed Nunn in the week after Russian forces were in retreat in northeastern Ukraine, a nation Russian President Vladimir Putin invaded on Feb. 24. Not only did Putin strike out in Kiev, he’s been through a series of military, economic and political humiliations. Not only was his enfeebled army in retreat in Ukraine, he failed to get full backing from Chinese President Xi. Indian President Modi lectured him on ending the war.

And 18 local officials from Moscow and St. Petersburg had called on him to resign. “We, municipal deputies of Russia, believe that the actions of its President Vladimir Putin are harmful to the future of Russia and its citizens,” the public statement said. “We demand Vladimir Putin’s resignation from the post of the President of the Russian Federation!”

Is Nunn witnessing history potentially repeating? Could Putin face a similar fate as Gorbachev, or worse?

“We’re in the most dangerous period we’ve been in since the breakup of the Soviet Union,” Nunn told HPI on Monday, comparing it to the Cuban Missile Crisis of 1962. “We have the threat of escalation, we have the threat of Russia bombing supply lines which would involve Poland and NATO. We have the increased dangers of cyber interference to command and control, (and) warning systems leading to blunder. The Russian invasion makes that all more likely. As you mention, we have the added danger of turning a nuclear power plant into a military base.

“It is a very dangerous time,” Nunn said.

On Tuesday in an address to the Russian people, Putin issued a threat that, while aimed at a domestic audience, jangled nerves in the West. Putin announced the mobilization – Russia’s first since World War II – just weeks after Ukraine launched a stunning counteroffensive that forced some of his troops to retreat. He noted “statements by some high-ranking representatives of the leading NATO states about the possibility of using nuclear weapons of mass destruction against Russia.”

“To those who allow themselves such statements regarding Russia, I want to remind you that our country also has various means of destruction,” Putin added. “We will certainly use all the means at our disposal ... It’s not a bluff.”

If there is to be a change of regime in Russia, it will most likely come in the form of a military coup, analyst of Russian politics Vladimir Juškin told ERR. “There are only two possibilities for change. A popular uprising would take longer, but a military coup is a more realistic option. They are already voicing their displeasure. Russia is peculiar in that everything happens at a moment’s notice. And it can happen as an uprising, when the people no longer have food, or as a military coup, when the army sees it is being turned into the scapegoat and refuses to go along.”

New York Times columnist Thomas L. Friedman writes in a Wednesday posting: “People talk, and every Russian soldier or Russian-speaking Ukrainian who sided with Putin has to be thinking: ‘Do I stay? Do I run? Who will protect me if the front breaks?’ Such an alliance is highly vulnerable to cascading collapse – first slowly and then quickly. Watch out. Why? Because Putin has already alluded several times to being willing to contemplate using a nuclear weapon if Ukraine and its NATO allies start to overwhelm his forces and he is staring at complete humiliation. I sure hope the CIA has a covert plan to interrupt Putin’s chain of command so no one would push the button. I am also aware that as part of this outcome Putin could be replaced by someone worse, someone from his ultranationalist right who claims that Putin did not fight hard enough or was sabotaged by his generals. Or, Putin could be replaced by a power vacuum and disorder – in a country with thousands of nuclear warheads.”

Retired Lt. Gen. Mark Hertling told The Bulwark’s Charlie Sykes earlier this week, “One factor that not a whole lot of people are saying much about is, truthfully, the Russian army is bad. As Ukraine has gone in one direction in terms of a positive transformation over the last 15 years, because of kleptocracy, corruption, poor training, poor leadership, lousy recruiting, and just the way they purchase and acquire equipment and treat their soldiers, the Russian army has deteriorated and gone in the opposite direction.”

Abbas Gallyamov, Putin’s former speechwriter, told CNN last Thursday, “Putin’s image is tarnished. The next thing which is going to happen in Russian politics within the next like several months, maybe up to half a year, is the elites will start looking for a successor.” The OVD-Info monitoring group counted at least 1,332 people detained at rallies in 38 different cities across the country after Putin’s morning address to the nation.

Konrad Muzyka, a defense analyst for Rochan Consulting, told the New York Times of collapsing Russian morale, “It is no longer science fiction to think that the war will end in a matter of weeks, months, and not years.”

New York Times Paris bureau chief Roger Cohen adds, “Mr. Putin cornered is Mr. Putin at his most dangerous. That was one of the core lessons of his hardscrabble youth that he took from the furious reaction of a rat he cornered on a stairwell in what was then Leningrad. His speech at once inverted a war of aggression against a neighbor into a defense of the ‘motherland,’ a theme that resonates with Russians.”

Sykes asked Hertling about “black swan events,” unpredictable sequences that can have severe consequences. What are the black swans that we should be keeping an eye out for?

“If something happens to the Zaporizhzhia nuclear power plant, that’s a scary event, but people are planning for what to do next, and they have talked about these things,” Hertling explained. “The Ukrainian army is [also] going to capture a lot of Russian prisoners, probably within the next week, if they haven’t already captured them.”

And then there is President Putin’s threat of using nuclear weapons, something Nunn now calls the “Putin Doctrine.” The theory is if Putin is backed into a political or military corner, he might unleash his nukes.

“The theory of nuclear deterrence of the past made this type of intervention less likely,” Nunn said. “In the case of the Putin doctrine, if one makes both nuclear and conventional war, I think it’s a reckless addition to the previous theories of deterrence.”

Here is the HPI Interview with Sam Nunn:

HPI: I remember you describing the time in late 1991 when you rushed to Moscow and literally witnessed the implosion of the Soviet Union from the gallery in the Duma. What are you seeing today with the Putin regime in Russia? Is there the kind of rot in the Russian military that reminds you of a similar set up in the old USSR? Are we witnessing a similar situation now?

Nunn: That whole series of events was not predicted. I don’t think this series of events that may transpire in the next year, or two or three are predictable either.

HPI: I agree.

Nunn: Barbara Tuchman wrote a book called “The Guns of August” and she wrote another book called “The March of Folly: From Troy to Vietnam,” which wasn’t as well known at the first one, but basically had 10 chapters of some of the worst decisions by leaders in the history that led to very serious disasters. I think if she were alive today she would write another chapter on Putin’s decision to invade Ukraine. I clearly think it is a march of folly. I think he is at a course of events that I believe will follow Afghanistan with the Soviet Union. He’s made some very, very bad mistakes that are tragic for Ukraine, tragic for  Europe, and extremely reckless and dangerous in terms of possible escalation, and I think in the long run, tragic for Russia. It is certainly not something I can predict. I do believe that the Afghanistan experience for the Soviet Union (left) the Soviet military very badly discredited. There were a lot of factors leading to the demise of the Soviet Union. More directly, it led to Gorbachev, not just becoming the leader, but I think it gave him a tremendous amount of space for taking on a radical new course of perestroika and glasnost. I think if the military and security apparatus had not been so discredited, they never would have given Gorbachev that much space. When they finally did attempt a coup, it was extremely inept and not supported. So it was a huge factor. What happened in the Soviet Union first – and it certainly a factor in the final breakup – I don’t think it was the dominant factor, it was the economic, but it was a factor.

HPI: When Gorbachev died this past summer, there were accounts that described the rot throughout the Soviet system that he encountered, putting him on his fateful course of reform that ultimately failed. It appears we’re seeing a similar situation within the vast Kremlin kleptocracy, where funds that were supposed to be rebuilding the Russian military ended up in the pockets of Russian oligarchs. Is there a parallel there?

Nunn: I think so, although the oil prices being up for almost the whole Putin regime has given him the impression of being a strong economic leader with a lot of the Russian people. Of course, oil prices are still up but I think it’s not an apples and apples situation.

HPI: Understood.

Nunn: Back in those days you did not have that kind of oil boom that you’re having now. Definitely the military ineptness is a really big factor. Putin misjudged his own military and his failure of intelligence or his failure to listen to the intelligence ... we do know that Putin has extremely bad reading or understanding of the intelligence, or he was badly misinformed as to Ukrainian reaction, to his own military’s capability, to his understanding of the will of NATO and the will of the United States, and certainly as to the leadership of Ukraine, as well as the courage and tenacity of the Ukraine people.

HPI: Was it a mistake during the Nunn-Lugar Cooperative Threat Reduction era to have Ukraine, Kazakhstan and Belarus give up their nuclear arsenals?

Nunn: I don’t think so. Ukraine never got control of their nuclear arsenals, in terms of operations. They did have physical control, but you have to remember the Soviet army had broken up and the Ukraine did not have much of a military force at that stage. I was in meetings with the Russian military where it was very apparent that Ukraine getting operational control strongly implies that never happened. I don’t think (it) would have been the same if they had tried to retain nuclear weapons. Something would have happened a long time ago.

HPI: Because Putin does not have to answer to a Politburo, and because there is no line of succession within the Russia Federation, Sen. Angus King has described Vladimir Putin as “the most dangerous man in history” because he controls this vast nuclear arsenal, has repeatedly threatened to use them, and now appears to be backed into a corner. Do you agree with Sen. King?

Nunn: We’ve had a lot of bad characters in history, so I wouldn’t be that sweeping, but a lot depends on what he does from here, on. A decision Putin is going to have to make is whether he’s going to have a protracted conflict or whether an insurgency will cross his border. Or will he do the sensible thing and at least abandon all the territories that he captured since February, and set in motion for the people of Crimea a sense of their own decision-making. Is he going to be able to do that without losing his job, or losing even more than his job? I don’t know the answer to that. It’s unknowable at this moment. He enjoys the prosperity of high oil prices and continues now. This situation is much more unpredictable.

HPI: This past week we’ve seen 18 local officials from Moscow and St. Petersburg and other municipalities call for Putin’s resignation, at great physical and legal peril to themselves. Do you see that as a shot across his bow to his rule from a domestic standpoint?

Nunn: I’m sure that is very troubling to him. He’s isolated himself a lot in the last four or five years. I think given the performance of his military and given that the military would be frustrated with the leadership and Putin would be frustrated with them due to the decision-making, the Russian soldiers on the ground don’t know why they are there; don’t know why they are fighting. So there is a lack of political leadership that goes beyond military command, it goes to the leadership of the country.

HPI: Do the attacks around the Zaporizhzhia Power Plant keep you up at night? I believe, for the first time in history, nuclear power plants are now in a war zone, leading to concerns about a catastrophic radiation incident similar to Chernobyl.

Nunn: It is reckless. I hope the IAEA at least going in there has helped the situation some, has helped ease the risk, but this being used as a military base with weapons being fired there and weapons being fired from there, whatever their source it threatens the electrical and water supplies which could lead to a meltdown without cooling. It’s a very reckless act. It would also be very damaging to Russia’s commercial leadership in terms of nuclear power. It puts that in real jeopardy. I think Putin’s implicit threats of the use of nuclear weapons is another reckless act and the repercussions of that are going to enduring. As I view it, we, and I mean both the U.S. and Russia, from time to time had nuclear doctrines that basically not only announced that we would use nuclear weapons in response to an attack, but NATO for years had a doctrine, and still does, and Russia has gone toward that which would be that an existential conventional attack would require a nuclear response. That’s been NATO’s view for a long time. Now what you have is a Putin Doctrine where, basically, a large nuclear power invaded a country that did not have nuclear weapons, and then added to that the threat of the use of nuclear weapons in the event that someone interfered with his invasion of a third country. Of course, that bluff was called in a very vivid way by the Biden administration and by our allies in Europe. If you think about it, in theory at least the threat of using nuclear weapons in response to a nuclear attack ... or an existential conventional attack ... is a new doctrine now that Putin has articulated. It has not succeeded in my view, but nevertheless the doctrine ... has basically made nuclear war and conventional war more likely in general beyond this particluar Ukrainian invasion. The theory of nuclear deterrence of the past made this type of intervention less likely. In the case of the Putin Doctrine, if one makes both nuclear and conventional war, I think it’s a reckless addition to the previous theories of deterrence.

HPI: Are we now in the most dangerous period since the Soviet collapse?

Nunn: We’re in the most dangerous period we’ve been in since the breakup of the Soviet Union. If you go back to the Cuban Missile Crisis ... it’s hard to compare, but without much doubt we have the threat of escalation, we have the threat of Russia bombing supply lines which would involve Poland and NATO. We have the increased dangers of cyber interference to command and control; warning systems leading to blunder. The Russian invasion makes that all more likely. As you mention, we have the added danger of turning a nuclear power plant into a military base. It is a very dangerous time.

HPI: What should my readers be watching? What tell-tales are you going to be looking at in the next six months on where all of this may be headed?

Nunn: Will Putin find a way to get out of Ukraine? That’s the fundamental question. A second question is when Zelensky says basically he’s going to take back every part of Ukraine territory, he’s said this implicitly, which includes Crimea. The Russians have large military forces there. That’s a real question. If Zelensky makes any kind of compromise that includes Crimea, then what do his nationalists do in Ukraine? Will he be able to continue with very strong and courageous leadership if he makes any kind of compromise on territory? A third question is if Crimea becomes the next geographic battleground, what do the U.S. and Europe do in terms of the understanding the huge escalation, but in terms of economic costs of what would undoubtedly be a tragic conflict? I see those questions as looming large, starting with Putin and going to leadership in Ukraine and then, third, European, NATO and U.S. reaction. Those are the things I’ll be watching.

HPI: Do you have any postscripts to the Nunn-Lugar Cooperative Threat Reduction era that come to mind in the relief of the current situation?

Nunn: Anyone who believes the world would be safer if Ukraine, Kazakhstan and Belarus had nuclear weapons is misreading history very badly.