Part of the cold war.
To thwart communist expansionism which was then known as part of the "Domino Theory" ; see related link .
Cambodia.
The nation (country) of Vietnam didn't exist during the Vietnam War. Nor was any nation called "Vietnam" fighting the US. There was a country called North Vietnam that defeated the Republic of South Vietnam in 1975. The US was allied to the RVN (Republic of South Vietnam).
Vietnam and Cambodia
It was fighting for democracy and against communism.
The Vietnam government claimed that about 400,000 Vietnamese were killed by America in Vietnam.
people
America fought against North Vietnam, in an unsuccessful attempt to defeat its invasion and conquest of South Vietnam.
viet cong.
in 1961
Stop communist aggression.
Australia's view was generally in line with America's view.
America didn't want to be part of: WWI, WWII, Korea, or Vietnam.
Cambodia.
Vietnam wasn't fighting anybody in 1964 because there was no country named Vietnam. There were two nations, one called North Vietnam and another called South Vietnam. Just like the states North Carolina and South Carolina or North Dakota and South Dakota in America...FOUR separate states! In 1964 North Vietnam became engaged in war with America; after the Tonkin Gulf naval battle(s) in August 1964.
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.
The NVA and the VC (North Vietnamese Army and the Viet Cong).
We were fighting for our freedom but America was the biggest threat to the communist countries