Just in time for its 60th anniversary, the Cuban missile crisis is trending big time. President Biden warned last week that Vladimir Putin’s threat to use nuclear weapons in Ukraine portends “the prospect of Armageddon” like no time “since Kennedy and the Cuban missile crisis.” And just as President John F. Kennedy coaxed Soviet Premier Nikita Khrushchev with a face-saving deal to pull his missiles out of Cuba in October 1962, Biden wondered what kind of deal might sway Putin to withdraw his troops from Ukraine now. “We are trying to figure out,” he said. “What is Putin’s off ramp?”...