Quora asks:

Will Putin resort to nuclear weapons now that it is becoming increasingly clear, from the many, many posts that I have read on Quora, that he has little or no chance of being victorious in Ukraine by means of conventional war?

and John Mark McDonald dispels the bunkum.

As someone who has studied nuclear war for close to forty years now, I am going to give you an answer that will blow your mind. Even if the entire Russian nuclear arsenal were used against Ukraine, it wouldn’t substantially change the course of the war. How could I possibly say that? Because, the power of nuclear weapons has been used as a boogeyman for so long that the actual power of a nuclear detonation has almost no relation to their actual destructive power. No nuclear power can afford to actually use one in combat because it would expose the mythical nature of nuclear weapons.

Nuclear weapons are hyped to the point that no one contradicts it when a media outlet publishes a statement indicating that even a single nuclear device will destroy the world. This is a blatantly, stupidly, obviously untrue, but never corrected. After all, two were used in WWII. BUT that is just the tip of the iceburg. I thought there had been a couple of hundred nuclear test that prove this point. I was off by over an order of magnitude. There have been nearly THREE THOUSAND NUCLEAR DETONATIONS ALREADY, that are either known or suspected and this has not effected the survivability of life on Earth even slightly.

Well then, how dangerous are nuclear weapons? Nuclear weapons, if they weren’t their own catagory, would be classified as incendiary weapons. They set stuff on fire. They set a lot of stuff on fire. In fact they can set things on fire as far as two miles away from the actual detonation. Besides this, nuclear detonation are very bright, capable of blinding people 20–30 miles away. This is only constrained by the curvature of the earth. They also create hurricane force winds as the air around the detonation expands and contracts. If you are outside and unshielded and within a mile of a nuclear detonation, you are going to die.

The problem here is that Ukraine is really big. I mean the size of Texas big. Cities there tend to be spread out in modern times and their larger ones cover over a hundred square miles. The average nuclear detonation are only burn 2–3 square miles of territory. A city the size of Kiev would take on the order of 200 warheads to cover the whole thing.

Which brings us to our next point. Modern cities are just not that vulnerable to incendiaries. Modern city centers and industrial areas are made of concrete and steel. Most of the damage in Hiroshima and Nagasaki was done because almost all the buildings were made of wood and paper. The initial blast set the city centers on fire which spread and ended up burning down most of the city. Modern cities are just not that vulnerable. In Ukraine, despite millions of rounds of being poured into their cities, not one of them caught fire and burned to the ground like the Great Chicago or Great London Fires in the 19th century or the fire storms of WWII. In the Japanese nuclear detonations, the brick buildings were still standing, despite being much less sturdy than modern buildings. This leads to the most surprising revelation about nuclear detonations: If you are not outside, you stand a good chance of surviving even within the blast zone. Nuclear blasts are mainly line of sight killers. The vast majority of “radiation” created by an nuclear detonation is infrared radiation, or heat the same as a gas stove or fireplace makes. Unless the building you are in is collapsed by the wind or you fail to leave if it catches on fire or you happen to be in front of a window with a direct line of sight to the detonation, you are probably going to be fine.

Thus we get to the real reason why Putin will not use nuclear weapons: they’re just not all that effective compared to the boogeyman that is in our collective imaginations. Were a nuclear missile to detonate over central Kiev, no one would believe that it was an actual nuclear blast because the city is still there and all the major buildings are still standing.

Secondly, he doesn’t have very many of them. The numbers given for the Russian nuclear arsenal are an outright farce. You get that number by taking of bombs that the USSR claimed to have built, and subtract the number used in their testing program. This leaves you with about 9,000 warheads. First of all, Russia doesn’t have nearly enough delivery systems to put those warheads on. The second problem here is that nuclear warheads have a very short shelf life. Nuclear warheads require a detonator made of conventional expolsives. These detonators are some of the most precision pieces of engineering in the history of mankind. A series of explosives has to go off in such a way that the core is hit by the same amount of pressure from all directions simultaneously. If any of those explosives are even slightly off, the nuclear warhead will not go off. You now have an extremely precise machine sitting around a core of material emiting hard radiation. Hard radiation is not friendly to machines. Nuclear warheads need to be rebuilt a least every five years and maintained a lot more often than that. Even with that, a twenty year old warhead is a piece of junk. It’s been more than twenty years since the Putin kleptocracy came to power. I’m sure that Russia has a number of Potemkin warheads that are kept in top shape for inspectors, but given the current Russian system, the Russian nuclear arsenal most likely resembles the Russian tank reserves: the bare minimum kept in service while the rest is a scrap pile.

Currently, the spectre of the vast Russian nuclear arsenal is the last card he has in his hand. If he were to actually use it, it would expose that he never had anything but a junk hand and bluffing to back it up.

I can recall reading a scientific calculation that contended that if you took all the nuclear weapons in existence, put them into a great big pile and fired them off, you would not get a hole as large and deep as the Grand Canyon.

General Kevin Chilton, in the Wall Street Journal, has alarming news about the state of America’s nuclear arsenal. Two American presidential administrations have responded to the end of the Cold War by completely abandoning the modernization and replenishment of the US stockpile of nuclear weapons.

Since the end of the Cold War, the U.S. nuclear weapons program has suffered from neglect. Warheads are old. There’s been no new warhead design since the 1980s, and the last time one was tested was 1992, when the U.S. unilaterally stopped testing. Gen. Chilton, who heads U.S. Strategic Command, has been sounding the alarm, as has Defense Secretary Robert Gates. So far few seem to be listening.

The U.S. is alone among the five declared nuclear nations in not modernizing its arsenal. The U.K. and France are both doing so. Ditto China and Russia. “We’re the only ones who aren’t,” Gen. Chilton says. Congress has refused to fund the Department of Energy’s Reliable Replacement Warhead program beyond the concept stage and this year it cut funding even for that. …

“We’ve done a pretty good job of maintaining our delivery platforms,” the general says, by which he means submarines, intercontinental ballistic missiles and intercontinental bombers. But nuclear warheads are a different story. They are Cold War legacies, he says, “designed for about a 15- to 20-year life.” That worked fine back when “we had a very robust infrastructure . . . that replenished those families of weapons at regular intervals.” Now, however, “they’re all older than 20 years . . . . The analogy would be trying to extend the life of your ’57 Chevrolet into the 21st century.”

Gen. Chilton pulls out a prop to illustrate his point: a glass bulb about two inches high. “This is a component of a V-61” nuclear warhead, he says. It was in “one of our gravity weapons” — a weapon from the 1950s and ’60s that is still in the U.S. arsenal. He pauses to look around the Journal’s conference table. “I remember what these things were for. I bet you don’t. It’s a vacuum tube. My father used to take these out of the television set in the 1950s and ’60s down to the local supermarket to test them and replace them.”

And here comes the punch line: “This is the technology that we have . . . today.” …

The general stresses the need to “revitalize” the infrastructure for producing nuclear weapons. The U.S. hasn’t built a nuclear weapon in more than two decades and the manufacturing infrastructure has disappeared. The U.S. today “has no nuclear weapon production capacity,” he says flatly. “We can produce a handful of weapons in a laboratory but we’ve taken down the manufacturing capability.” At the height of the Cold War, the U.S. produced 3,000 weapons a year. …

these already-old weapons aren’t going to last forever, and part of the general’s job is to prepare for their refurbishing or replacement. “Think about what it’s going to take to recapitalize or replace those 2,000 weapons over a period of time. . . . If you could do 10 a year, it takes you 200 years. If you build an infrastructure that would allow you to do 100 a year, then you could envision recapitalizing that over a 20-year-period.”

There’s also the issue of human capital, which is graying. It’s “every bit as important as the aging of the weapon systems,” the general says. “The last individual to have worked on an actual nuclear test in this country, the last scientist or engineer, will have retired or passed on in the next five years.” The younger generation has no practical experience with designing or building nuclear warheads.

Read the whole thing.