No, just that they didn't care what the cost was. We could have bombed the dikes, flattened Haiphong, nuked them back to the stone age and they still would have fought. What position were we in? Locked into an alliance with a country that really didn't want to fight. Why should we fight if the ARVN didn't?
How do you know they "didn't care" what the cost was? I'll tell you why: because you've been sold that line by socialist jelly-brained defeatists such as Cronkite, Fonda, and Moyers.
A common sense understanding of human nature teaches the opposite. Of course they cared. But our feckless politicans always gave them just enough time and space to catch their breath until their fifth column of traitors in the US could undermine the war effort and cause us to lose our will and morale.
A US victory with relatively little loss of life (on both sides) was surely achievable. We could have broken their will and morale, but the longer we dithered the more difficult and bloody that task became.
We should have fought like Patton--not McClellan.