Conservatives highly supported the Vietnam War. You can see it in shows like All in the Family, where Archie Bunker is insulted at the idea of a draft-dodger visiting his house for dinner.

To many older Americans at the time, they were still in the mindset of WWII: that you defended your country when it called on you to do so, and without question. In many Americans' eyes, this was a war where your country was helping to keep another country free from Communism. People had heard horror stories coming in from North Korea and the gulags in the Soviet Union. How people lost their children or got shot for failing to stay in line politically and religiously.

In that vein, people were also still riding on the high of Allied victory in WWII. Many thought America (or their respected Allied country) was unbeatable. Vietnam was a swift kick in the gut to that notion. It was not just something shocking: it was embarrassing. Nobody really likes to admit that they lost at something, so they'll come up with excuses, however legitimate or not. You looked bad in front of others, and you failed to help somebody. No one ever wants to be honest with themselves about that.

Whether this mentality affected today's far-right, nationalistic ideology is a little more complicated. History rarely has one direct cause - it's much more like a series of events and grievances. Nuance is the key thing to remember. The dogmatic attitude of some "war hawks" did not necessarily reflect all pro-war citizen's views. You also have to include the culture wars at the time, economic developments, as well as the evolving concept of masculinity and national attitudes.

To sum it up: it's yes to the first question, but only sort-of to the second. People are people, and no movement is cut-and-dry.