Your vaunted ability to preach the verdict of history from the results of real events somehow fails when the lessons don't mesh with your preconceptions, do they?

These events simply cannot be denied, and they are quite self-evident:

The countries were supposed to fall like dominoes if the Reds won.
The Reds won.
The dominoes never fell.

And we didn't put out any fires, we started a whole bunch of new ones instead: we were the only palefaces in Vietnam, Laos, AND Cambodia, and we militarized the rest of the region to support our activities there. Could it be that maybe that was the plan all along? Oh, and don't forget, we killed a million people, most of them civilians, while we were at it.

It's that simple. I'll be the first to admit that we can perceive trends and learn lessons from history, but it doesn't operate by rigid laws, like physics. And it doesn't stop operating just because the USA decides to intervene.

We screwed up in Nam big time because we failed to see what was going on due to our own ignorance and stubborness in foreign affairs, and because our infantile fanatical anticommunism prevented us from taking advantage of real opportunities to frustrate genuine Red conspiracies.

We mistook a a nationalistic attempt to reunite a country, a civil war, for a global geopolitical move by the Soviets and Chinese. Sure, the North was Communist, but the war was not part of any coordinated Communist plan. In fact, both Russia and China tried to talk Ho out of fighting because they didn't think they could win it and they would lose their one foothold and client state in Southeast Asia. They didn't think the Vietnamese could beat the Americans and they certainly didn't want the US pouring troops into the region and threatening their southern flank.

Vietnam and China had a long history of conflict and distrust that didn't stop when both became Red. Did you know the Viets forcibly evicted 30,000 ethnic Chinese and confiscated their property? China was no friend of Vietnam, a fact Russia was feverishly trying to exploit since they were no friends of China either. And none of this seemed to make any impression on our myopic Commie-baiting politicians.

Instead, we missed a great opportunity. We had promised Ho Chi Minh during WWII assistance in getting independence from the French if he would help us against the Japanese, and Ho had great respect for the US. He worked with us, trusted us, and we lied to him. We sold him out because the French threatened to not join NATO if we didn't help them get their rubber colony back. If we had played our cards right we could have had a Communist ally in SE Asia, like the Phillippines, a development that would have frustrated Chinese ambitions in the region for a century.

After we got our butts kicked out, Vietnam and China wound up fighting a bloody war, and the US and China actually worked together to help the monster Pol Pot because we both wanted to embarrass the Vietnamese--purely out of childish spite. LBJ and Nixon screwed up in Southeast Asia as badly as Bush screwed up in the Middle East.

And the French eventually dropped out of NATO, and today, we make rubber out petroleum. So much for the lessons of history.