Does Putin’s alert change risk of nuclear war?

Russian President Vladimir Putin’s implied threat to turn the Ukraine war into a broader nuclear conflict presents President Joe Biden with choices rarely contemplated in the atomic age, including whether to raise the alert level of U.S. nuclear forces.

This turn of events is all the more remarkable for the fact that less than a year ago, Putin and Biden issued a statement at their Geneva summit that seemed more in keeping with the idea that the threat of nuclear war was a Cold War relic. “Nuclear war cannot be won and must never be fought,” they agreed.