Rbit, You are in delusion, I think.
Do you remember that we INHERITED the Vietnam war from France? That was both a CIVIL war (Catholics against Buddhists, with possibly a few other things going on) AND a war against foreign GRINGO colonialists.
You could have nuked Hanoi and all it would have done was turn us into butchers and turn those we fried into martyrs.
And, on the US side, there was never anything to "win". We couldn't win economically. And we couldn't win morally. Certainly, few believed Our Masters that losing Vietnam would create an existential threat to the average citizen of the United States.
But all that is only the tip of the iceberg.
http://wtfhappenedin1971.com/
Vietnam was really the beginning of the end for the United States. And by the time we pulled out, with our tail between our legs, VIETNAM HAD ALREADY BANKRUPTED THE UNITED STATES.
Everything that came after, including the rapid transition of the US from the largest creditor in the world to the largest debtor nation, was arguably made inevitable by the decision to go kill people in Asia...for no sufficient reason.
You want to blame the politicians, but the average citizen of the US never wanted that war to begin with, there was no consensual moral not economic imperative, and there was no "booty" sufficient to pay for it, even if we had genocided the Vietnamese to the last person and taken over the whole territory.
A good question, which I don't know enough to answer, is "What made Vietnam different from Korea"? Dividing Korea in two, created a stable and economically powerful S. Korea.
Maybe someone here can educate me further?