I watched this several years ago when it turned up on TV one night. I hate to admit it but it actually educated me about the Cuban missile crisis. None of my high school or even college courses ever made it as far as the cold war so anything I know of it was essentially self learned. Horrible thought since I was born in '69 and many people my age don't know squat about the cold war.
Anyway, I was pretty awed by the movie. Devane is fantastic as JFK. You really end up sort of feeling the phenomenal tension of knowing that we really did almost have missiles hurled at us. I agree with last post that this film could be used in classrooms.