As I understand it after 1967 the RVN forces were preparing to go on the offensive by eithger invading the North or by going into Cambodia and Laos to destroy VC strongholds and supply lines. The problem was we didnt support them and the RVN by themselves had no expereince with large scale troop movements at the division level. I think if we had allowed them to go on the offensive , even let them cross the DMC and invade NV, things would have changed.
The American goal was the establishment of a stable Republic of Vietnam (aka South Vietnam) that was capable of defending itself from the Democratic Republic of Vietnam (aka North Vietnam). Pretty much the situation we got in Korea.
It was unlikely to happen though. There was no regime in Saigon that could form the basis of a stable government. The Diem regime was strong enough to eliminate any rivals but not strong enough to form a stable government itself. So we had to prop it up. And when Diem’s regime was overthrown, the Thieu regime that replaced it was even weaker.
Ho was a communist. But he put nationalism ahead of communism. He would have been willing to accept a multi-party system for Vietnam as long as it was independent.
But that wasn’t going to happen. Some Americans did recommend backing Ho and the nationalists in Vietnam. But the French were committed to maintaining their colony. So the United States had to choose which country was more important to American interests and we chose France over Vietnam.
Unfortunate as it was to the Vietnamese, it was probably the right choice from America’s point of view. We ended up making an enemy out of Vietnam but that was less damaging to American interests than making an enemy out of France would have been.
Our big mistake was later on. France finally acknowledged it couldn’t hold Vietnam and left in 1954. At that point there was no longer any wider need for us to stay. We should have withdrawn with the French. But by that time, we had been using anti-communism as a reason to support the French and that was theoretically still a valid reason for us to stay even if the French left.
Pol Pot? 
Why do you say that Pol Pot was a result of the American defeat?
Because when the ARVN invaded Cambodia in 1972, the US air force bombed most of the Cambodian countryside to deter COSVN, and backed Lon Nol to overthrow the Monarch of that country, and thus radicalised a whole section of the populace to throw their lot in with the Khmer Rouge.
So a whole country was thrown to the wolves to cover the US troop withdrawal.
This is really it. The only way the war could have been won was if the South had a government that could gather and hold solid support of its own people. We can debate why that didn’t happen or even if it could have happened, but without it, there was no hope.
I think the exact same thing can be said of Afghanistan, but that’s another thread.
The Hanoi Communist government (you know, the ones we were fighting) ended up being the who ended the killing fields and got rid of Pol Pot.
Brains.
I don’t think there’s any evidence of that. The Viet Minh was entirely Communist. When it set up North Vietnam, it was originally in coalition with non-communist parties, but it soon purged them. When it took over South Vietnam, it purged non-communists there. When did Ho or the North Vietnamese ever show any actual interest in a multi-party system?
What the OP describes is the American version of the stab in the back myth. It doesn’t stand up to scrutiny, though it persists because the war’s planners and their ideological allies refuse to accept defeat. You see the same thing with Iraq.
The U.S. could’ve invaded the North, if you think fighting a land war with China sounds peachy. In fairness, it kinda worked in Korea (except the South Koreans weren’t also shooting at us). Even assuming a conventional victory, it’s not clear what the next step would be since resistance would have most likely continued absent a genocidal response (this was McNamara’s position iirc). Maybe a multi-decade occupation force. America’s enemy in Vietnam wasn’t just communist stooges in Hanoi but a popular nationalist insurgency fighting against what they perceived as Western colonialism (French, America, same diff) and their puppet rulers in the South. The answer would be hearts and minds, but in retrospect it’s not clear how to do that. We’re still not very good at that.
After Tet there were internal discussions of increasing U.S. troop numbers, but even the hawks understood this would just lead to a more violent stalemate because the North had plenty of warm bodies and wasn’t about to give up the fight. American planners kept trying to figure out how to “break their will” with bombings and shows of force but it never happened. The Vietnamese had been fighting for independence since the '40s. These people were making bullets in their basements and bringing supplies through the jungle on bicycles. They were in it to win it.
South Korea was run by autocrats and suffered from coups and general political turmoil until the late '80s. So South Vietnam was kinda on that road already.
This is, IMHO, the biggest problem. The south just had no government that the people could put any trust in. And the people in power were obviously only interested in what they could get for themselves.
To win, and this is just an opinion, it was necessary to invade the north, preferably close to Hanoi where they would be forced to stand and fight. Yes, I know, Russia and China and all that. But who knows if they would really have intervened to any extent. There’s been a long history of animosity between Vietnam and China (they had their own war in 1977ish) and Russia is a long way off.
If we could have forced them into anything approaching a set piece battle they would have had major problems. While their artillery, small unit moral, weapons, and general capabilities were very good ours were too. And we had air power. The importance of which has to be seen to be appreciated.
As an example look at Khe Sanh. With all the artillery they put on the base, the first use (I think) of tanks by the north, the element of surprise, and something like 3 or 4 to 1 numerical superiority they never came close. They were pounded day and night until they gave it up as a bad job. Of course they didn’t stay whipped. They were very good at waiting, licking their wounds, and forming up to try again another day. Probably our weakest point.
The idea of making them stand and fight in large numbers, again just MHO, was a death knoll for them. In my experience in Vietnam if they could be held in place* you could pound them to death with artillery, helicopters, and jets.
But it wasn’t going to happen for obvious political reasons.
*They knew this too. It seemed to me at the time that they were very careful to only attack at ranges over 250 yards or under 50. Over 250 yards and they could get away before the planes, helicopters, or artillery could get there. Under 50 and it was just too dangerous to us to use them. But in between our firepower could hold them there, and then they were largely fucked.
Without disagreeing with anything else, the South fell because the money was withdrawn, not because the soldiers were withdrawn.
Yup, that sounds about right, we could have done that. Why didn’t we?
Thing is, South Korea’s government wasn’t particularly strong or stable either until the 1990s. Their military wasn’t capable of resisting the north on paper until the 1980s, and who knows if they actually would stand and fight even today despite conventional superiority. But if we assume a similar trajectory in Vietnam, the South would have been ready to exist with a minimal US force there sometime around 1995. THe US just wasn’t willing to make that kind of commitment in the face of guerilla resistance. If Kim Il Sung had known that, he probably would have used different tactics in the 1950s than he did in Korea and been successful.
By what standard or measurement do you make this claim?
What year are we talking about? 1945 or 1975? You can’t project back from what they did after fighting thirty years of war to what they would have agreed to back before that war began.
Ho had lived in America and was a strong admirer of the United States. He actively sought American support. And he certainly indicated he’d be willing to negotiate with other Vietnamese factions. His only condition was he wanted an independent and united Vietnam. He would have been happy to agree to a multi-party system when he would have rightly believed that the communists would be the majority party elected into power.
We dropped 7 million tons of bombs on Vietnam. That’s more bombs than were dropped during World War II by everyone. We used carriers, B-52 bombers, fighters, tanks, helicopters.
You seem to suffer from the same sort of mistaken line of thinking of folks like Westmoreland and McNamara in that we could “win” by continuing to double down on brute force.
But were the bombs dropped at the right time? At the right place? If you virtually wipe out the enemy, then you win militarily. There may be political ramifications after the war, I agree.
South Vietnam finally fell not because it ran out of money but because its army ran away.
See also:
Iraq.
1946-1956, mostly, the period of time starting with Ho allowing the French back into Northern Vietnam and ending with the conclusion of the Land Reform Program. I don’t know if Ho was an admirer of the US or not. I do know that the party wasn’t willing to tolerate other parties except in a sort of puppet role, and they, under Ho’s leadership, crushed any sort of non-Communist movements or parties.