> Heavy counter-culture movements in the country
> A country no one knew existed until the army came
> Terrible humid climate that made everyone miserable
> Extreme use of drugs and alcohol.
> Pointless bloody battles fought in places that seemed random
> No clear goals, frontlines and even enemy formations
Way too much stuff got in the way to make it one hell of a war.
Failure to learn from he past.
The US was fighting a colonial resource war, the Vietnamese were fighting a war of national liberation.