Are Putin’s nuclear threats really likely to lead to Armageddon?

The past week has seen a rapid escalation in nuclear rhetoric, beginning with Vladimir Putin’s threat to use “all forces and means” to defend newly seized territory in Ukraine and ending with Joe Biden’s warning of “Armageddon” if Russia crosses the nuclear Rubicon.

However, the realities underlying the menacing vocabulary are a far greyer area than the bluster suggests. It is far from certain that Putin would be prepared to be the first leader to use nuclear weapons in wartime since 1945, over his territorial ambitions in Ukraine. If his primary goal is to stay in power, that could be exactly the wrong way of going about it.

Even if he did issue the launch order, he has no guarantee it would be carried out. Nor can he be absolutely sure that the weapons and their delivery systems would work.

On the US side, despite the US president’s apocalyptic language at a private fundraiser on Thursday night, it is not at all inevitable that Washington would respond to Putin’s nuclear use with nuclear retaliation. Past wargaming suggests there would be vigorous debate within the administration to say the least.

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Like US presidents, Putin is normally accompanied by an aide carrying a briefcase with codes used to authorise a nuclear launch. In the US it is called the football, in Russia it is the cheget. In the Russian system, the defence minister and the chief of the general staff have their own chegets but it is believed that Putin can order a launch without them.

However, the cheget is relevant for the strategic nuclear forces, the intercontinental ballistic missiles (ICBMs) launched from land or sea, or long-range bombers. Because they need to be launched within minutes in case of enemy attack, the warheads need to be deployed, mounted on the delivery systems.

Any nuclear use in Ukraine would be likely to involve non-strategic, or tactical, weapons with shorter-range delivery systems, and which are usually (but not necessarily) less powerful than strategic arms, though on average they are many times more powerful that the Hiroshima or Nagasaki bombs.

The US only has one kind of tactical weapon, the B61 gravity bomb, of which there are about a hundred in Europe and a similar number in the US, according to the Federation of American Scientists (FAS).

FAS estimates Russia has 2,000 tactical weapons, in very many shapes and sizes for use on land, sea and air. The weapons are not deployed on missiles or aircraft, but kept in bunkers in storage sites dotted around Russia. There are 12 national storage sites, known in Russian military parlance as “Object S”, one of which is in Belgorod, right on the Ukrainian border.

There are also 34 “base-level” sites, closer to the delivery systems. In a time of crisis, warheads would be moved from national to base-level sites – and up to now western intelligence agencies say no such movement has been observed.

Any such movement would be carried out by the 12th main directorate of the Russian armed forces, which has the job of storing and maintaining the warheads and then delivering them in specialised trains or trucks to base-level sites, or directly to the unit designated to launch them.

Pavel Baev, a military researcher who worked for the Soviet defence ministry, said that Putin cannot count on these weapons actually working.

“Most of these warheads stored there are very old,” Baev, now a professor at the Peace Research Institute Oslo, said. “Without testing it’s really hard to say how suitable they are because many of them are past their expiration date.”

Baev added that it was also far from clear that the Russian can successfully pair old warheads with the much newer delivery systems that would have to be used, possibly 9K720 Iskander or Kinzhal hypersonic missiles.

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Not all analysts have such a dim view of the state of the tactical arsenal. Pavel Podvig, who runs a research project called Russian Nuclear Forces and is a senior research fellow at the UN Institute for Disarmament Research, said: “There’s a maintenance protocol. There are ways of checking whether a weapon is in good health.”

What may be more likely to break down, however, is the chain of command if Putin gave such an alarming and extreme order.

“It’s one thing to follow the order to start a ‘special military operation’ that you understand will be over in three days,” Podvig said. “It’s another thing to accept the order to drop a nuclear bomb. There’s a sense that this kind of order would be universally considered as criminal. I think the calculation would change.”

The Russian leader is already reported to be facing dissent from his inner circle. Taking the leap to nuclear use could stretch his authority to breaking point.

“I think it would be prohibitively risky for any commander-in-chief to give this order because if you give the order and it’s not executed, it backfires,” Baev said.

If Putin decided to gamble everything and if his military officers went along with him and managed to detonate a weapon in or around Ukraine, then Biden and his team would be faced with choices that all modern US presidents have hoped they would never have to make.

US warnings to Russia in recent days have been vague on what the response would be, saying only that it would be “catastrophic”. The White House needs to keep its room for manoeuvre, depending on what Russia does, whether it is a “demonstration” blast over the Black Sea or the Arctic, or the bombing of a Ukrainian military target or – the worst-case scenario – a city.

In 2016, the Obama administration carried out war gaming exercises to test its communications channels and decision-making process in the event of a Russian use of a tactical nuclear weapon. There were deep disagreements that led on some occasions to heated arguments.

“The debate broke down along two pretty important lines,” said Jon Wolfsthal, who was Barack Obama’s special assistant and senior director at the national security council for arms control and non-proliferation.

The first question was whether “the US or Nato needed to respond militarily”.

“In the game, the answer was no. The US was winning the conventional war,” Wolfsthal, who writes a Substack column titled BoomBoomBoom, said.

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The counter-argument was that the US could not afford not to respond with nuclear weapons.

“There were those who said if you don’t use nuclear weapons, two terrible things will happen. One is: all of our allies will doubt our commitment,” he said. “The second is: if you don’t use a nuclear weapon in response, how do you deter Putin from going nuclear again? You needed nukes to re-establish deterrence.

“We never answered that. We never settled that debate,” Wolfsthal said.

The 2016 war game – first reported in The Bomb, a book by Fred Kaplan – was played twice, at the level of cabinet secretary, the “principals” and by their deputies. The principals voted to respond with a nuclear strike, but not on Russia, in the hope of avoiding an all-out planet-ending nuclear exchange. Instead they struck Belarus, arguing it was a “belligerent non-combatant”.

The deputies voted not to respond with nuclear weapons, arguing that the US could win with conventional weapons and that nuclear use would make it much harder to isolate Putin internationally. Two of the officials who pushed that option are now in senior positions in the Biden administration: Colin Kahl is the Pentagon’s policy chief, and Avril Haines is the director of national intelligence. After the war games were over, Haines suggested having T-shirts printed with the slogan “Deputies Should Run the World”.

The 2016 war game was set in a Baltic nation, so inside Nato and under its protective nuclear umbrella. Ukraine stands outside that umbrella.

Ernest Moniz, Obama’s energy secretary is reported to have voted for a nuclear response in 2016. He would not comment or even confirm the war game took place, but he said Ukraine was a very different case.

“I would say that if the line is crossed to nuclear use, there has to be a very, very strong response,” he told the Guardian. “But that response doesn’t have to be nuclear.”

The key question is more likely to be whether the US and its allies should respond with devastating conventional firepower, as Poland’s foreign minister, Zbigniew Rau, and the former CIA director David Petraeus have suggested. But that would transform the war into one between Russia and Nato, in which escalation to a nuclear exchange could become hard to stop.

According to Eric Schlosser, the author of a book about the nuclear establishment, Command and Control, the Pentagon’s Defence Threat Reduction Agency (DTRA) conducted another war game in 2019 focused on Russian nuclear use in Ukraine. That wargame appears to have been updated, suggesting it is in constant use. The results in 2019 are top secret, but as Schlosser wrote in the Atlantic, one of the participants told him: “There were no happy outcomes.”