US/allied enemies were:
1. WWI-Central Powers
2. WWII-Axis
3. Korea-Chicom & North Koreans (Chicom=Chinese Communists)
4. Vietnam-NVA & VC (North Viet Army & Viet Cong (guerrillas)
Axis goes to the WWII group.
Wrong war. WW2 Axis was Germany, Japan, and Italy.
After the war, there was a reunification of Vietnam. So the answer is "One country".
Vietnam , America , and Russia
The major countries that were Axis in WWII are Germany, Italy and Japan.
The Vietnam War was part of the cold war. The cold war was between governments (Nations/Countries).
North Vietnam/VC vs allies
North Vietnam won them.
The countries that were actually "physically" involved, and were bombed or had US aircraft crash into them, whether they were "officially" in the war or not, were: Lao's, Cambodia, North Vietnam and South Vietnam.
The main three countries of the Axis powers in World War 2 were Germany, Italy, and Japan.
The Soviet Union (USSR) supplied North Vietnam, and the US fought for South Vietnam.
The Allies were democracies and only went to war reluctantly. (Many say that they waited too long). The Axis countries were dictatorships and fought a war of aggression.
The axis powers were Germany, Italy, Vietnam, and Japan.