Will Russia break 8-decade global taboo against using nukes?

Russia’s assault on Ukraine and its veiled threats of using nuclear arms have policymakers, past and present, thinking the unthinkable: How should the West respond to a Russian battlefield explosion of a nuclear bomb?

The default U.S. policy answer, say some architects of the post-Cold War nuclear order, is with discipline and restraint. That could entail stepping up sanctions and isolation for Russian President Vladimir Putin, said Rose Gottemoeller, deputy secretary-general of NATO from 2016 to 2019.

But no one can count on calm minds to prevail in such a moment, and real life seldom goes to plan. World leaders would be angry, affronted, fearful. Miscommunication and confusion could be rife. Hackers could add to the chaos. Demands would be great for tough retaliation — the kind that can be done with nuclear-loaded missiles capable of moving faster than the speed of sound.

When military and civilian officials and experts have war-gamed Russian-U.S. nuclear tensions in the past, the tabletop exercises sometimes end with nuclear missiles arcing across continents and oceans, striking the capitals of Europe and North America, killing millions within hours, said Olga Oliker, program director for Europe and Central Asia at the International Crisis Group.

It’s a scenario officials hope to avoid, even if Russia targets Ukraine with a nuclear bomb. But for former Sen. Sam Nunn, a Georgia Democrat who over nearly a quarter-century in Congress helped shape global nuclear policy, the option of Western nuclear use has to remain on the table.

“If President Putin were to use nuclear weapons, or any other country uses nuclear weapons first, not in response to a nuclear attack, not in response to an existential threat to their own country … that leader should assume that they are putting the world in the high risk of a nuclear war, and nuclear exchange,” Nunn said.

For U.S. officials and world leaders, discussions of how to respond to a limited nuclear attack are no longer theoretical. In the first hours and days of Russia’s invasion, Putin warned Western countries to stay out of the conflict, saying he was putting his nuclear forces on heightened alert.

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