Space Race 1961: Soviets sent the first person to orbit the earth. They had beaten the U.S. in the space race. The Soviet success in space worried Kennedy because he believed that this would make people believe that communism was better than capitalism.
Cuban Missile Crisis 1962: American spy plane spots construction of soviet missile in Cuba. Kennedy authorized a naval quarantine around Cuba and demanded Khrushchev to stop the construction.
Kennedy Assassination 1963: Kennedy was in Texas to help get support for his reelection campaign. He traveled through Dallas in an open top limousine when shots were fired and he was killed.