Certainly.
A war is determined explicitly by the presence of conflict. If there was not conflict in Vietnam, there would not have been a war.
Yes, there have been major conflicts throughout history, such as World War I and II, the Vietnam War, and the Iraq War. These conflicts have had significant impacts on countries and societies around the world.
They funded the war.
McKinley was in office during the Spanish American War.
At the end of the Vietnam War, Congress refused to support South Vietnam any longer.
No, of course. Vietnamese's cause is just.
No, it wasn't because nobody won any land.
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.
Mostly stopping charges when there was no time to reload, and in any eyeball-to-eyeball conflicts.
Unlikely.
See answer to same question, following this one.
Yes they did have conflicts, and were constantly at war with their neighboring tribes.
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).