Wagner’s Revolt in Russia Stirred Fears of a Nuclear Crisis

A defiant mercenary commander’s fleeting march on Moscow over the weekend sparked concerns among Western intelligence analysts about the stability of Russia’s military command and the security of the nation’s vast nuclear arsenal.

U.S. officials say they haven’t seen any difference in the disposition of Russian nuclear forces since Yevgeny Prigozhin, leader of the Wagner paramilitary group, led his private army toward the nation’s capital. Wagner forces seized a key military facility in southern Russia on Friday and pushed northward through Russia’s central Voronezh region, where Russia maintains a nuclear-weapon storage facility under the command of the 12th Chief Directorate of the Ministry of Defense (MOD). The dramatic putsch ended Saturday when Prigozhin reached a deal with the Kremlin and halted the convoy about 120 miles south of Moscow.

Though the immediate crisis was averted, U.S. intelligence remains vigilant, looking for signs of vulnerability to the world’s largest stockpile of nuclear weapons. The officials say the U.S. military has no reason to adjust conventional or nuclear-force postures and emphasized the Biden Administration continues to maintain long-standing, established hotlines and channels with Russia on nuclear issues. But the officials say Russia has a special responsibility to keep command, control, and custody of its nuclear forces and to ensure that no actions are taken that imperil strategic stability.

“Of course, when we’re dealing with a major power, and especially a major power that has nuclear weapons, that’s something that’s of concern,” Secretary of State Antony Blinken told CBS on Sunday. “We haven’t seen any change in Russia’s nuclear posture. There hasn’t been any change in ours, but it’s something we’re going to watch very, very carefully.”

Read more: Fearing 3-Way Arms Race, U.S. Seeks Nuclear Talks With Russia and China.

Russian Foreign Minister Sergei Lavrov told the state-owned RT television network Monday that Lynne Tracy, the U.S. ambassador to Russia, contacted the Russian Foreign Ministry during the revolt to ensure the security of Russian nuclear weapons and the safety of U.S. diplomats working inside the country.

Military and nuclear-security experts believe there was little risk Prigozhin or his forces would attempt to obtain the weapons at the Voronezh-45 base or any other installation throughout the country. But the short-lived uprising against Russian President Vladimir Putin’s government nonetheless highlights concerns in Washington about the safety and security of Russia’s nuclear weapons.

It’s the stuff of nightmares for an American president: the loss of a single Russian nuclear warhead into the hands of a terrorist group, rogue nation, or other bad actor. Securing Soviet “loose nukes” has been a top priority for Republican and Democrat Administrations alike since the Soviet Union’s collapse in 1991. The U.S. spent billions of dollars aimed at establishing methods to prevent the loss, theft, or sale of the Soviet arsenal of 27,000 weapons, along with its bomb-grade plutonium and uranium.

Russia’s nuclear-storage system is anchored by 12 central storage sites, such as Voronezh-45, and about 35 base-level storage facilities, says Pavel Podvig, a nuclear security and arms-control expert who leads the Russian Nuclear Forces Project. Under Russian doctrine, he says, weapons are stored separately from the planes, missiles, and systems that deliver them. “The storage sites are reasonably well-guarded, and I don’t see why Wagner would divert resources to get something they cannot use and that can get them in serious trouble,” Podvig says.

Read More: Putin Suspended the Last Remaining Nuclear Pact With the U.S. Here’s What Happens Now.

Long-term nuclear weapon storage sites are located inside areas that can be described as a military base within another military base. The areas are constantly surveilled and surrounded with barbed wire fences and guard posts. The warheads are inside concrete and steel bunkers. Affixed to the weapons are electronic safeguards, known as permissive action links, which are code-accessed and designed to rendered the weapons unusable if an unauthorized person attempts to arm them.

The seizure of a nuclear weapons site would escalate a dramatic domestic dispute into a full-blown global crisis. But Olga Oliker, the International Crisis Group’s director for Europe and Central Asia, says there aren’t many scenarios in which a paramilitary force like Wagner would be able to operationalize the nuclear weapons or find a strategic use for them.

“The first is really set up to be quite difficult. The second is just hard to imagine,” she says. “Russian weapons and facilities are under solid control and there’s no evidence that Wagner or anyone else is looking to capture them. Not only would they be tremendously difficult to gain use of, there’s no real logic for doing so. What would they do with them?”

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Forces with the 12th Chief Directorate of the MOD, which are charged with protecting, maintaining and—if called upon—delivering Russia’s nuclear weapons aren’t likely to open its door to Wagner, says Andrey Baklitskiy, a senior researcher who studies weapons of mass destruction at the United Nations Institute for Disarmament Research. “The forces of 12th MOD main directorate have reasons to protect them really well,” he says. But Baklitskiy admits that if Wagner kept up its push to Moscow, and had the fighting somehow escalated into “a full scale civil war, we would be in an uncharted territory.”

U.S. intelligence had picked up signs that the rift between Prigozhin and Russian Defense Minister Sergei Shoigu could break open in a sudden and dramatic way, officials said, but they had not anticipated how little resistance Russian forces would put up in the face of Wagner’s advance. The mercenaries’ military vehicles pushed eastward from Ukraine to the southern Russian city of Rostov-on-Don, where they briefly occupied the military headquarters, then went north. They were about two hours from Moscow when the announcement came that a deal had been struck.

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