All tanks and jets built to fight the USSR did fight in the Vietnam War and ended up being combat tested and evaluated there. The results of those tests are today's tanks and jets (to include the Top Gun schools of the USN and Air Force; where air to air combat is conducted).
Vietnam is a communist country. US forces are not allowed there. However, US veterans visit Vietnam as tourists every year.
No.
It was obvious North Vietnam wasn't going to quit; so the US declared victory and went home (from the GI's perspective).
They started the Vietnam War
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).
Few US citizens heard of the word "Vietnam" until their draft notice appeared in the mail.
Ally refers to wars; the US is not at war with any nation. The US is friendly with nations and participates in free trade with many countries, Vietnam is one of them.
Nothing
When the US withdrew from Vietnam in 1975, it did nothing to repair Vietnam, on the principle that Vietnam was a member of the Soviet bloc, and their communist allies, the USSR and China, were the ones who were responsible for any needed international assistance to Vietnam. It is much easier, from a political viewpoint, for the US to help a defeated enemy, as it did with West Germany and Japan and Italy, following WW II, than it is to help a victorious enemy. After fighting so desperately to prevent communist North Vietnam from taking over South Vietnam, the US was not then going to help communist Vietnam to rebuild after the war. The communists won the war, they therefore could rebuild themselves. Since the end of the Cold War in 1990, relations with Vietnam have improved, but are still not very close. The US does not like to lose.
The govornment frequently lied about what was going on
The goal of the Vietnam War was to stop the spread of communism. As such, the US felt the need to stop the influence of communist North Vietnam, which entailed supporting South Vietnam in any way possible.
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