France may have suffered the fate they built for themselves. Regardless, the France of now is not the 'French resistance' France, its become soft in it's nanny statism. Except for Jean Reno, he kicks ass. 
We choose to intervene, and failed to learn from their mistakes. It didn't help us win friends there when the OSS helped supply and train the Viets to fight the Japanese, leading them on that they would gain independence, only for us to allow the French to take over Vietnam again as a colony. To add salt in the wound, the French who ran Vietnam before they turned it over the Japanese where Vichy who sold out to Germany. One can see why why the Viets didn't trust anyone to have their best interests at heart when they were used by all the big powers. It's just a pity they choose communism as a Ideology.
If our leaders had read Bernard Falls books on the French Vietnam war, they would have learned that it was impossible to beat insurgents with modern mechanized forces, no way to win the hearts and minds of a people who were tired of having everyone occupy their country, and most importantly, there was never a so-called "Domino strategy" where the VietMinn had any intetion to play as a proxy puppet for either China or the USSR to make the rest of Southeast Asia into a communist satellite like the Warsaw Pack.
Ho Chi Mihn was a commie, sure. They did bad things. And I hate commies. But he and his cronies only cared about one thing, and that was uniting Vietnam and kicking out the French, US, and everyone else out to become an independent nation. Both the USSR and China had brushed aside Ho Chin Minh decades before, when he was a eager follower of communism. Vietnam and China hated each others guts going back thousands of years. The only reason those two nations helped Vietnam was to fight a proxy war against us. So in short, they used Vietnam, and Vietnam used them, with no love lost after the conflict.
If South Vietnam truly cared to fight to stay free, I could see helping them like we helped the South Korea. But they were corrupt as hell, stole from their own people, and had no sense of nationalism outside of Saigon. Everybody outside of the cities were tribes and small villagers who were only paid attention to by thier leaders when taxes were due.
We should have stayed out of it, or declared war to invade North Vietnam and defeat them in six months with everything we had. But we didn't want to incite China, so we fought a half-assed war that guaranteed we would lose fighting a war of wills and attrition that favored the commies.