Hardly a day goes by without Russian President Vladimir Putin waving his nuclear bludgeon to cow Ukraine and the West.
Is he crazy? Maybe, because launching such weapons would break a 77-year-old nuclear taboo.
Ever since the United States dropped atomic bombs on Hiroshima and Nagasaki, the unthinkable has been kept in check through some 200 conventional wars — even where nuclear powers were involved on one side or the other. Only once did the Soviet Union and the U.S. come close to the edge of the abyss — exactly 60 years ago during the Cuban Missile Crisis. Why did they pull back and what are the lessons for our time?