Question

How did the reception of Vietnam veterans by the American public differ from the reception that World War I and II veterans received?

Answer 1

Most of the US did not support the Vietnam war, so there was already hatred surrounding the military. The US government decided that they would film the war, allowing the American people to see what they were paying for. These American were fooled by the government as the government censored what they could to make it seem like the Americans were winning the war, although they were in fact losing. Leaked videos and pictures flooded America, and the truth started to come out. American soldiers were told to massacre villages (couldn't tell the Vietcong from the citizens), and in result, the American people called their own veterans "baby killers". For the veterans of this war, there was no welcome back party, no honour from their people, just hate.
This differs from the World Wars as the veterans are seen as heroes. They left their home to go fight with other countries to Europe from "evil". They won the war, and returned peace and democracy to Europe. The fact that the Americans lost the Vietnam war, AND that their efforts to contain communism failed (Vietnam is communist), it hurt the American image.
In the end, the Vietnam war and WWI & II are very different wars with different circumstances. Vietnam ended badly, and the World Wars didn't (for the Americans).

Answer 2

While the general public was celebrating and treated the WW1 and WW2 veterans well, they were generally angry at the Vietnam veterans, mistreated them, called them names, etc.

The difference between the two was that the WW1 and 2 was viewed as saviors of the world, helping to win a battle that they didn't exactly want to fight, but were dragged in

while, the Vietnam soldiers were losing a fight that they weren't wanting to be part of. (its worse that they were fighting a war the public didn't want to be part of, and on top of that, they were losing)

hope this helps.