South Vietnam was called the "REPUBLIC of South Vietnam." Everyone in those days just called North Vietnam...NORTH VIETNAM.
Presuming you mean the government supported by the US: The Republic of South Vietnam.
How about "Conflict and Combat: The Vietnam War"
ARVN=Army Republic of South Vietnam. NVA=North Vietnamese Army.
Australians.
China
Vietnam has a communist government.Communism is a social structure in which classes are abolished and property is commonly controlled, as well as a political philosophy and social movement that advocates and aims to create such a society.
Agent Orange
No US General conducted such operations. See website: Vietnam War
There were two hot battles that took place during the Cold War. The Korean Conflict and the Vietnam War were associated with the superpowers. The Cuban Missile Crisis was pretty key. The other was the Berlin Blockade.
This 21st century generation is probably "evolving" the 1960's term of "Hawk" into a "supporting the troops" meaning. Hawks during the Vietnam War were, "bomb them back into the stone age!" types, that also advocated invading North Vietnam and using atomic bombs to win the war. Doves during the Viet War were, "peace at any price." It is worth noting that the term "war hawk" is not exclusive to the Vietnam War, but is used to designate supporters of ANY armed conflict.
Cambodia emerged from the Vietnam conflict and the rise of the Khmer Rouge as the Peoples Republic of Kampuchea until 1993. The official name of the country is the Kingdom of Cambodia.
US Military newspaper: Stars & Stripes