No, they aren't.
The answer is yes, South Korea was in the Vietnam War!
Which Korea and which Vietnam? Today's Vietnam or the old North and South Vietnam?
Yes, South Korea is an ally of the Republic of Vietnam. During the Vietnam War, South Korea helped the United States and the Republic of Vietnam to fight against the communists. The Republic of Vietnam was helped by South Korea, by the United States, by Thailand, by Taiwan, by New Zealand, by Australia, by Singapore and by Malaysia!
Containing it=Keeping it from spreading. Example 1: Keeping Communist North Vietnam from conquering South Vietnam; which failed (South Vietnam was consumed by communist North Vietnam). Example 2: Keeping Communist North Korea from conquering South Korea; which succeeded (South Korea was preserved).
North Korea and south Korea and also North and South Vietnam
Yes, Republic of South Korean Servicemen fighting in Vietnam were referred to as ROK's...the ROK Army (Republic of South Korea).
New Zealand, US, South Korea, South Vietnam, Philippines, Thailand.
US, New Zealand, Australia, South Korea, South Vietnam, Thailand, Philippines.
ROK (Republic of South Korea); Philippines, Thailand, US, New Zealand, Australia, South Vietnam.
Like in Vietnam, North and South had different opinion about government. North Korea is currently a communist country and South Korea is currently a democracy.
US, Australia, New Zealand, Thailand, Philippines, South Korea, South Vietnam; verses North Vietnam and the VC.
Australia, New Zealand, South Korea, Philippines, Thailand, and South Vietnam.