Evgeny Buzhinsky has spent much of his professional life with the threat of global nuclear destruction hanging over his head. A lifelong Russian military officer, he earned his PhD in military sciences in 1982, just as the Cold War was entering its most dangerous period, and served in the Soviet general staff during an arms race that several times came perilously close to triggering a nuclear war that neither side wanted.

Buzhinsky retired a lieutenant general in 2009, after a long career on the Russian general staff, including several years heading the Russian Defense Ministry's international treaty agency, which brought him into frequent contact with European and American generals over some of the most contentious issues of the post–Cold War era. He now heads the PIR Center, a well-respected Russian think tank that focuses on military, national security, and arms control issues.

Amanda Taub and I met last week with Buzhinsky at a cafe in Moscow to ask him about a topic that is being increasingly discussed in certain policy circles in Washington, Moscow, and NATO's headquarters in Brussels: the fear that tensions between Russia and the West could spiral into an unwanted war, perhaps even nuclear war. As a true veteran of the Cold War, not to mention someone who had only recently left the highest ranks of the Russian military, he seemed like the right person to ask.

"Ukraine, for Russia, is a red line"

Gregarious, bear-sized, and clearly accustomed to dealing with Westerners from his years working on international treaties, Buzhinsky surprised me by waving off two fears that are most pronounced among Western and some Russian analysts: a military conflict in the NATO-allied Baltic states bordering Russia, or an accidental collision with Russian military flights buzzing along NATO airspace with their transponders switched off. But he nonetheless foresaw war as a possibility, however undesirable.

If Ukrainian forces attempted to retake the territory in eastern Ukraine (Donbas) held by pro-Russia separatist rebels, he warned, the Russian military could very well declare war and march on the Ukrainian capital of Kiev, whatever the costs. He also described potential dangers from the military buildup in Europe — particularly American missile defense there — and discussed when Russia's nuclear doctrine would or would not allow the use of nuclear weapons.

Buzhinsky is not a government spokesperson, nor was he always the most objective as an analyst, as would be expected. But his view seems to reflect, at least to some degree, that of the Russian military leadership, which remains one of the most important and least understood actors in Russia's tensions with the West — not to mention a group with control over thousands of nuclear warheads.

What follows is a partial transcript of our conversation, edited and condensed for clarity.

"If Russia starts a war, it never stops until it takes the capital"

Max Fisher: I had a question for you about Ukraine. We've talked to people in Russia from a number of perspectives and political parties about their view of the crisis in eastern Ukraine and how Putin has handled it. But something we hear very little about is how the Russian military general staff views the crisis. I'm curious if you have any sense for how it's seen.

Evgeny Buzhinsky: For me, it seems to me that people in Donbas decided — because, you see, the dominant majority of the population are Russians. The plans to Ukrainize the east and southeast of Ukraine — this stupid law that everybody in Ukraine should speak only Ukrainian, although 75 to 80 percent in their day-to-day lives speak Russian — of course, this prospect frightened people. And they decided that it would be as easy as it was in Crimea. But the cruelty with which the [Ukrainian] nationalists suppressed the pro-Russian activists in Odessa, that kicked off everything, and afterward, of course, the situation went out of anybody’s control. A year ago, I was absolutely convinced Russia would never interfere militarily. I'm not talking about volunteers, instructors — I mean interfere with regular forces. Now I'm not so sure. In the West, they say there is a peace party [among the Ukrainian leadership] headed by [President Petro] Poroshenko, and a war party of [Oleksandr] Turchynov and [Prime Minister Arseniy] Yatsenyuk. That's not true. All of them are from the same party, and they don't want a political settlement. For them, political settlement is a defeat. They all are for military victory. As Putin said twice, we will not allow the physical extermination of the people of Donbas. I fear that it may — well, it's unpredictable. A war with Russia in Ukraine — if Russia starts a war, it never stops until it takes the capital. That's all the Russian wars.

Max Fisher: Is that something you're worried could happen in Ukraine?

Evgeny Buzhinsky: Yes. Well, I don’t exclude it. And then I could not predict the reaction of the United States and NATO.

Max Fisher: What would be the trigger for that happening?

Evgeny Buzhinsky: The trigger? A massive offensive on the Ukrainian side. The size of Ukrainian armed forces versus the people of Donbas, they are not comparable. Ukraine is stronger; it has much more equipment, personnel. The defeat of Donbas would definitely mean the physical extermination of a lot of people.

Max Fisher: So you think if that were to happen, then Putin will have no choice but to intervene, even if it meant going all the way to Kiev?

Evgeny Buzhinsky: Yes, definitely. He said twice publicly, "I won't let it happen." As he is a man of his word, I am sure he will.

Max Fisher: How do we avoid that?

Evgeny Buzhinsky: The US administration should press Kiev [for restraint] until we agree to political settlement of the issue, not a military solution.

Max Fisher: I think they're seeking a political settlement, aren't they?

Evgeny Buzhinsky: I don't think so. All this talk about supplying lethal weapons.

Max Fisher: So that, to you, that signals an American desire to push Kiev to end the conflict militarily?

Evgeny Buzhinsky: Frankly, that's a general opinion in the Russian Federation and among the military, especially.

Max Fisher: From what you’re saying, it sounds like if NATO troops were to intervene directly or were to heavily arm the Ukrainian military, then that could provoke a response that could be very dangerous.

Evgeny Buzhinsky: Of course. It seems to me that the Ukrainian goal is not just deliveries of sophisticated systems. It's the presence of the US crews and personnel on the front line in the east. And that is very dangerous, because the first US military man killed, wounded, captured — the reaction, for example, in Georgia [in the 2008 war], until the first Russian peacekeeper was killed, Russia did not interfere. Three were killed, and the order was given. Dangers in the Baltics

Max Fisher: That makes me wonder about the Baltic states, about Estonia and Latvia. They seem very stable, but there are NATO military vehicles parading 300 yards from Russia’s western border. Does that introduce a similar risk, in your view?

Evgeny Buzhinsky: Of course, it's not very friendly. Next time we'll have a parade 200 meters from the Estonian borders with the airborne division, and we'll conduct some kind of landing on our territory.

Max Fisher: Is there a concern that even if what everybody's doing is trying to signal deterrence, the signals could be misconstrued and there could be space for an accident or an unwanted escalation?

Evgeny Buzhinsky: After they joined NATO, and the alliance decided to deploy a squadron of fighters in Lithuania on a rotational basis, we warned our partners that it could cause some accident. The international airspace between Estonia and Russia is so narrow that one day our pilot may be forced to land on the other side. And it happened to a Russian pilot. I remember when our pilot, an inexperienced pilot, lost his way and interfered into Lithuanian airspace and was forced to land. He spent two, three weeks there while we negotiated his release. The same might happen now, but the pilot could be American or German, and who needs that? They say it's a demonstration of solidarity.

Amanda Taub: Do you think that on the American side there's a good understanding of Russia's positions?

Evgeny Buzhinsky: No. No. The Ukrainian crisis was very much influenced by the spoiled relations between Obama and Putin. Because otherwise, they would have talked to each other. You mentioned the Cold War. In the Cold War time, there were definite red lines on both sides. And both sides knew there were red lines and tried not to cross them, tried to not even come close. Ukraine, for Russia, is a red line. And especially a Ukraine that is hostile to Russia is a definite red line. But the US administration decided that it's not. [The Americans believe that] Russia will never dare, Putin will never dare, to interfere.

Amanda Taub: I think from the US side there's a similar perception that Russia thinks the US is weak. That Russia thinks the US is sort of unwilling to defend Ukraine.

Evgeny Buzhinsky: Objectively, the US is not weak. We could not stand on an equal footing with the United States using only conventional weapons. Only on nuclear [weapons] do we have parity, only on strategic nuclear [weapons] do we have equal footing. As for conventional warfare, we do not, and we recognize that, and we are trying to catch up. Nuclear deterrents and nuclear dangers

Max Fisher: With NATO building up in Europe and especially in the Baltic states, does that necessitate some kind of Russian buildup to maintain parity?

Evgeny Buzhinsky: There is a nuclear equilibrium, the strategic balance. As for conventional forces, we'll never catch up with the combined capability of the United States and the [NATO members] in Europe. Nobody, as far as I know, is thinking about plans to catch up.

Max Fisher: Is the nuclear parity enough to make up for the conventional imbalance?

Evgeny Buzhinsky: Yes. Because with non-strategic nuclear weapons, Russia has the advantage. The United States does not need non-strategic [tactical or battlefield-use nuclear weapons] to defend its own territory. But the Russian Federation has 17,000 kilometers of land borders and quite a few states with either nuclear capability or missile capability [nearby]. For us, it's a means of regional deterrence to compensate our relative weakness in conventional [capability].

Max Fisher: I wanted to ask you about tactical nuclear weapons. I feel like I do not have a good understanding of whether Putin believes there could be a scenario in which there is a limited nuclear use, which is to say there could be one or two battlefield uses of tactical nuclear weapons without things escalating into global nuclear conflict.

Evgeny Buzhinsky: Well, of course, it's impossible for me to say what Putin thinks. Okay, Moscow is destroyed and Washington is destroyed, and they both say "Okay, that's enough"? It doesn't happen in real life.

Max Fisher: But I would be surprised to learn that Russia had not developed any plans at all for a limited nuclear use. Because the Russian nuclear doctrine says if Russia is at risk of being completely overrun by a conventional military attack, then Russia could use nuclear weapons. But in that scenario, wouldn't it be preferable under the Russian nuclear doctrine to have a limited battlefield nuclear use?

Evgeny Buzhinsky: Well, if Russia is heavily attacked conventionally, yes, of course, as it's written in the doctrine, there may be limited use of non-strategic nuclear weapons. To show intention, as a de-escalating factor. But Europeans don't have the capability to massively attack [Russia]. So it's on the United States. If the United States decides to massively attack the Russian Federation, it should be ready to meet all the consequences, limited or unlimited. The missile (defense) race in Europe

Max Fisher: One of the things you worked on in your time with the military was arms control agreements. You're outside the government now, of course, but it seems like arms control issues have become more contentious since the Ukraine crisis. Is that the case?

Evgeny Buzhinsky: Well, it has become difficult, but not because of the Ukrainian crisis. It started with the Bush administration and with [Bush's effort to introduce] missile defense, which actually undermined strategic stability [in Europe]. When President Bush announced his plans to withdraw from the ABM treaty, President Putin's response was that it doesn’t pose a danger to Russian deterrence capability for the time being. [Note: in 2003, Bush withdrew the US from an anti-ballistic missile treaty that forbid certain types of missile defense.] What he meant is that if the plans had been limited to North America, it would be all right. But since he went beyond, that started to pose a threat to Russia’s deterrence capability.

Max Fisher: What is it about missile defense that you think has been so contentious?

Evgeny Buzhinsky: Missile defense is an issue of strategic balance. The old metaphor is two gladiators with swords of equal length. One acquires a shield. What's the way out for the second one? Either to have a shield or to get a second sword. That's the answer. So it's strategic balance. It's deterrence potential on both sides. If the US decided to acquire a missile defense shield — and not a limited one, it's a global one — then what does Russia have to do? Well, actually, to acquire more anti-anti-missile defense. That means the development of more sophisticated nuclear warheads with the capacity to overcome missile defense. And so on. "Obama modified the plans, but still we are worried"

Max Fisher: In that view, is this US program defensive, or is there a concern that it might also be offensive?

Evgeny Buzhinsky: Well, you see, it's funny when you differentiate between defensive and offensive. You see, in all the military academies, in all textbooks, missile defense is qualified not as a defense against the first strike. It's the defense against a retaliation strike, the second strike, which gives the illusion to the attacking side that it may survive retaliation strikes. Because you cannot repulse a first strike with any missile defense, or you've got to have tens of thousands of warheads.

Max Fisher: So there is a fear that, at least in terms of technical capability, American missile defense could be used as a cover for an American first strike against Russia?

Evgeny Buzhinsky: Of course. Russia has 1,500 warheads. During a first strike, half of that would be destroyed, so only 750 left. Then Russia decides to deliver a retaliation strike, and in this case missile defense may be quite effective.

Max Fisher: Are there other forms of American or NATO military buildup in Europe that are seen as potentially offensive?

Evgeny Buzhinsky: Of course, we know the plans. First of all, there was the [US] plan to dig up silos in Poland, which is a very, very bad idea. And radar, which are to be transported to the Czech Republic. Obama modified the plans, but still we are worried, especially the third and fourth phase where ground-based AEGIS [missile defense] systems with MK41 universal [missile] launchers are to be placed in Poland and then the deployment of AEGIS cruisers in the Baltic and North Seas. Some of our experts, for example General [Vladimir] Dvorkin [who oversaw nuclear issues in the Russian military], say it's impossible to intercept our missiles, even with those cruisers and Aegis ground-based that were placed in Poland. My answer for today is yes. With a speed up to two and a half kilometers per second, [missile defense] cannot intercept them. [Note: He is referring to Russia’s planned hypersonic missile, the BrahMos II, which would travel up to Mach 7 — 2.4 km/s]. But as far as I know, as far as we know in Russia, the plans [for missile defense] are to go to seven kilometers per second, and in this case they're quite able to intercept our missiles being launched from the European part of our country. The F-35 "fantasy"

Max Fisher: What about the F-35?

Evgeny Buzhinsky: Well, F-35. I prefer to speak about real things, not about plans.

Max Fisher: Okay, so you've been to Washington. You're familiar with how this works. Even still, the US is spending a lot of money on developing this stealth fighter jet, and even if it ends up being just a fantasy —