"Unfortunately there is substantial minority of the US population that believes we could have won the Vietnam war"
It happens to be the same ignorant minority who think the South could have won the Civil War (and still will).
Yep these same people are romanticizing and wrapping in nostalgia a cause whose goal was the perpetuation of a monstrous evil. And then when they actually lost they went home and stopped blacks from voting, and lynched and burned them alive by the hundreds.
Good analogies, there is kind of a sick pattern going back even to the civil war.