Communist infiltration into South Vietnam.
It was Ho Chi Minh.
no
Vietnam is currently ruled by the Communist government led by President Nguyen Minh Triet.
diem was the communist leader of north Vietnam.
The "Cold War" was a battle against communism. North Vietnam was a communist country trying to take over South Vietnam which was NOT a communist country. The US was helping South Vietnam fight North Vietnam so that communist North Vietnam could NOT take it over.
The communist super-power's goal was expanding communism; Hanoi was trying to expand communism by attempting to take over the "Republic" of South Vietnam, a non-communist country (nation). North Vietnam was in keeping with communist expansion; which is why the Chinese Communists/USSR supplied Hanoi with war material & training.
The Vietnam War
The French Indochina War most likely led to the (so called) American Vietnam War. Because the French war divided up the country into TWO nations; North & South Vietnams. When the communist led North Vietnam attempted to take over (conquer) South Vietnam... this led to US involvment.
Just like Korea, North Vietnam is a communist state under Ho Chi Minh, while South Vietnam is run under a non-communist pro-American government led by Ngo Dinh Diem and later Nguyen Van Thieu.
Vietnam has a one-party socialist republic system of government. The Communist Party of Vietnam is the dominant political party, and the government is led by the General Secretary of the party. Although there are other political parties allowed, the Communist Party holds significant power.
The policy of Soviet (Communist) containment meant that the communists would not be allowed to take over South Vietnam. We would destroy the communists in South Vietnam and contain them to NORTH Vietnam.