Castro is a military dictator but would have no vested interest in starting a nuclear war. It was a political move. Cuba could become dust if he were to launch such a missile. I believe he's a despot but not crazy. Who knows if he really had nuclear armaments in those delivery systems? I personally doubt it. It's like Iraq's WMD's.

The idea behind Communism as practiced in the USSR or Cuba is more
about enforcing that ideology on the rest of the world, not obliterating it. That latter doesn't make sense for a Communist ideologue.

Frank