Work on your grammar pls.
I think you mean to ask what other war would have a similar effect on the USA as loosing the Vietnam war did if the Vietnam war was won somehow?
Well, Korea comes to mind of course but that happened before Vietnam. But the same idea is there, if it takes too long and too many casualties because the US army has no idea how to fight the enemy you could see the same kind of protests and uproar that Vietnam caused. Of course the North Koreas would have to eventually beat the USa militarily in order for the chaos to be complete. I doubt they would have the strength to do that. It would more likely mean a war between USA and China.
I think practically any proxy war could go awry like Vietnam did. It depends on how unprepared and naive they enter it.