The US policy in Vietnam boiled down to one thing: body count. US only real measure of success was how many Vietcong/PAVN they killed; and because they had no way of telling the difference -- nor did they care much -- this effectively meant "kill as many Vietnamese as possible" (they were encouraged to consider any casualty as VC, overrepresenting their numbers). And to top it out, they engaged in massive forced resettlement, pillage, rape, destroyed foliage and the ecosystem, and poisoned the land.
Think about it.
Americans living in Vietnam claim the Vietnamese don't hate them. Even ex veterans visiting the country report this. That's pretty amazing all things considered.