Americans by and large don't mind sacrificing their young as long as they get good value for it. With Vietnam they saw soldiers sacrificed for utterly pointless

Americans by and large don't mind sacrificing their young as long as they get good value for it. With Vietnam they saw soldiers sacrificed for utterly pointless things like defending Khe Sanh or taking Hamburger Hill (both were abandoned right after victory), all while their leadership was telling them they weren't even seeking military victory. Meanwhile half the country was calling the troops babykillers (not without reason) and young people being drafted into the mess were faced with the moral choice of going to prison or running away to Canada (with the associated accusations of cowardice and shame brought on their family by idiots) or turning off their conscience and shipping off to Vietnam to kill some people posing absolutely no threat to their freedom or way of life. No matter how you look at it, it's way more complicated than boiling it down to US deaths.