"Putin might do the unthinkable"

But among the specialists who study Russia’s nuclear arsenal, there has been a long-running debate about another scenario — the possibility that Russian forces might use so-called “tactical” nuclear weapons, which have shorter ranges and smaller explosive yields, to seize a battlefield advantage, especially in conflicts they are losing. This new doctrine, in Strangelovian fashion, is known as “escalate to deescalate” or “E2D.” It started in 2014, when an official Kremlin document raised the possibility of a nuclear reprisal to a conventional strike if “the existence of the state itself is threatened.” The following year, Putin said that he had considered putting Russian nuclear weapons on alert to protect ethnic Russians in Crimea, which was annexed by Russia in violation of international law. In 2018, Trump’s national security team thought that E2D was a serious enough threat to warrant mention in the Nuclear Posture Review. That document predicts a scenario where “limited first use” of tactical nuclear weapons “could paralyze the United States and thereby end a conflict on terms favorable to Russia.”

In an interview with Insider, General James Clapper, the former intelligence chief, said he agrees with the assessment that the Russian military now views itself as having a lower threshold for the use of tactical nuclear weapons. “The Russians were driven to this,” he told me, “because the current Russian Army is, comparatively, a shadow of the Soviet Army.” If your traditional military is weak, in other words, tactical nuclear weapons offer a major form of compensation.