It was transparent hokum, but there were clever and original bits - the concept of being able to transfer your personality into a giant blue being, the better to interact with a whole tribe of giant blue beings, was good.
I felt the allegory pertained to anything the Yanks have done since their push West into the territory of the Plains indians, including the Black Hills of Dakota, Vietnam, Iraq, Afghanistan, the whole lot.
As for the floating hills, I painted those exact hills in my teens. The painting was stolen from a Tesco staff locker room when I was a Trainee Manager (shelf stacker). I bet the bastard who nicked it is now working as a concept guy for Cameron.