@UnparalleledMonster, I disagree, we could have bulldozed the NVA and could bulldoze Daesh, _IF_ we were willing to cause massive civilian casualties as well. Once the NVA knew we wouldn't hit an AA battery on top of a hospital, the war was lost for us. Daesh doesn't just take over cities to have women to rape and supplies to plunder. They do it because they know we haven't had the stomach to level entire cities since WWII. Dresden, Hamburg, Tokyo, Nagasaki, Hiroshima ... MacArthur was willing to go to that extreme in Korea, but Truman wasn't.
I'm not saying MacArthur was right or wrong. But when your enemy is willing to do anything (e.g. use civilians as shields) and you're not (e.g. kill the civilians to kill the enemy), you're already at a tremendous disadvantage. It isn't that the military _couldn't_ use superior firepower to crush the NVA or Daesh, it's that the collateral damage would be so high, the politicians won't let them.
(In case it's not clear, I am NOT advocating the U.S. take a "win at all costs" strategy against Daesh. I'm stating what I view as the reality of war.)