Visited Vietnam last year and currently rewatching Tour of Duty (and for the record the central highlands of Vietnam do strongly resemble the hills of southern California, it's not all jungle). So Vietnam, justified war? South Vietnam was ruled by an autocratic series of regimes that paid mere lip service to democracy, was corrupt and occasionally brutal to it's own citizens. HOWEVER. North Vietnam was indisputably MORE corrupt, didn't even pretend to pay lip service to democracy and was incredibly brutal and repressive towards it's own citizens (and continues to be so to this day). What's more the North was invading the south, not the other way around. After the fall of Saigon both Laos and Cambodia are also conquered by the communists whilst Thailand, Malaysia, Indonesia and the Philipines fight communist insurgencies for decades afterwards just as the domino theory predicted (thankfully China and Vietnam fall out in the 70s, even fighting a short border war whilst the Soviet Union shifts it's focus to Angola, Nicuragua etc). Millions are killed by the communist regimes, not only in Pol Pot's killing fields but whole nations of Montgnard tribesmen who helped the US are exterminated. Millions more are thrown into concentration camps or fled overseas as boat people. And if the Allies had won? Today the south would probably be like South Korea and the North, well, leave it to your imagination. So morally justified? I say yes, winnable? Perhaps?