The New York Times reports:

The old nuclear order, rooted in the Cold War’s unthinkable outcomes, was fraying before Russia invaded Ukraine. Now, it is giving way to a looming era of disorder unlike any since the beginning of the atomic age.

Russia’s regular reminders over the past three months of its nuclear might, even if largely bluster, were the latest evidence of how the potential threat has resurfaced in more overt and dangerous ways. They were enough to draw a pointed warning to Moscow on Tuesday from President Biden in what amounted to a tacit acknowledgment that the world had entered a period of heightened nuclear risks.

“We currently see no indication that Russia has intent to use nuclear weapons in Ukraine, though Russia’s occasional rhetoric to rattle the nuclear saber is itself dangerous and extremely irresponsible,” Mr. Biden wrote in a guest opinion essay in The New York Times. “Let me be clear: Any use of nuclear weapons in this conflict on any scale would be completely unacceptable to us as well as the rest of the world and would entail severe consequences.”

Those consequences, though, would almost certainly be nonnuclear, officials said — a sharp contrast to the kind of threats of nuclear escalation that Washington and Moscow pursued during the Cold War.

Such shifts extend well beyond Russia and include China’s moves to expand its arsenal, the collapse of any hope that North Korea will limit — much less abandon — its cache of nuclear warheads and the emergence of so-called threshold states, like Iran, which are tantalizingly close to being able to build a bomb.

During the Trump administration, the United States and Russia pulled out of arms treaties that had constrained their arsenals. Only one — New START, which limits both sides to 1,550 deployed strategic weapons — was left in place. Then, as the Ukraine war started in February, talks between Washington and Moscow on what might replace the agreement ended abruptly.

With the Biden administration stepping up the flow of conventional weapons to Ukraine and tensions with Russia high, a senior administration official conceded that “right now it’s almost impossible to imagine” how the talks might resume before the last treaty expires in early 2026.

Last summer, hundreds of new missile silos began appearing in the Chinese desert. The Pentagon declared that Beijing, which had long said it needed only a “minimum deterrent,” was moving to build an arsenal of “at least” 1,000 nuclear arms by 2030.

The commander of United States Strategic Command, the military unit that keeps the nuclear arsenal ready to launch, said last month that he was worried Beijing was learning lessons from Moscow’s threats over Ukraine and would apply them to Taiwan, which it similarly views as a breakaway state.

The Chinese are “watching the war in Ukraine closely and will likely use nuclear coercion to their advantage” in future conflicts, the commander, Adm. Charles A. Richard, told Congress. Beijing’s aim, he said, “is to achieve the military capability to reunify Taiwan by 2027, if not sooner.”

Other administration officials are more skeptical, noting that Russia’s saber rattling failed to deter the West from arming Ukraine — and that the lesson China may take away is that nuclear threats can backfire. [Continue reading…]