What's notable about Castro's conduct during the missile crisis is that whilst it was actually Khrushchev that made the decision about locating the missiles in Cuba as an arguably proportionate response to America's own missile locations, it was Castro's private correspondence that urged Khrushchev to be prepared to actually use them.

(Khrushchev, not known as one of the Cold War's more pacifistic figures, responded that he found Castro's suggestion quite disturbing)