The U.S. felt threatened against Cuba because Cuba now had missiles. The CIA had an army forming in Guatemala and were training soldiers there so that Cuba didn't know that the U.S. was apart of the invasion.
A conference that was held after WWII. The U.S, Soviet Union, and England discussed the division of Germany, formation of U.N., German war reparation, entry of Soviet forces in Japan, and the future of Poland. This started the Cold War.