Question

How did John F Kennedy's actions during the Cuban Missile Crisis help prevent a nuclear war???

Answer 1

All through out the Cuban Missile Crisis, the U.S. was in def con 5. Which is 1 step away from Nuclear warfare. If JFK was less cool about everything, the world would have gone into nuclear warfare. I suggest watching this vid it gives you more of an idea of what it was like :) 

https://www.youtube.com/watch?v=bwWW3sbk4EU

Answer 2

It made a peace between two nations.