Yeah, true. The North Vietnam, the VPA, was a solid front, a coherent conventional army. Of course, the Viet Cong were mostly guerillas in the Southern Vietnam, but that is an another story. Still, even with all as it was, even if US did manage to destroy the VPA, the war would be far from won, due to the insane numbers of partisans remaining. And I find it stunning that US could not make significant progress against the conventional VPA. I guess the terrain really was that bad...

Wait, volunteer military? Haha, good joke. After almost exactly 60,000 American dead, I doubt very many wanted to join... Logically, the US population is so large that it should have found enough willing recruits, but why then did they institute the draft? Because they needed more men who did not sign up I suppose. Which means the sentiment really was that opposed to war. And the lack of backbone is as much of a problem as a lousy military. Look at the Russian Empire in WWI. Internal strife is more dangerous than enemy munitions. Many wars are won by words, not weapons, and the DRV won that war.
There was not a very logical mindset. There would have been plenty of volunteers to draw from but the US still thought it was dealing with WW2 and everyone would be willing and honored to serve (which is of course a generalization). Volunteers made up a pretty solid percentage of troops in Vietnam. However, it was mostly draftees i'm sorry to say who whined and ******* their way through the war and committed atrocities they blamed their superiors on. And while i said it had a major impact, and it did the anti-war movement was relatively small. Mst americans disapproved of the anti-war demonstrators but were silenced by the vulgar and very public displays to demonstrators put on. The anti-war movement was made up of alot of cowardly draft dogers in my personal opinion though my opinion is clouded by family ties.

What the Us truly suffered from was zero clearly defined goals. What was the point? To preserve democracy, sure that's grand but give me something tangible. Therefore, the average American soldier had nothing to fight for, nothing to really hold in his mind as what he wanted, unlike his father in WW2. Not to mention the issues with being unable to invade the north and our inability to fight a guerrilla movement (which i believe we have improved on). America did not tactically or strategically lose Vietnam, they lost because of a vibrant and loud anti war movement back home and poorly defined goals.