Yup. Black Hats and White Hats.

One thing about invasions, though. Any indigenous populace has a moral right to defend themselves against a foreign invasion of their homeland. That is inviolable. It doesn't mean that every individual on the invading side is a "bad" person....certainly not!...but their cause is wrong if they are trying to take over and rule/exploit someone else's ancestral lands. Land belongs to the people who are born on it...not to some political or mercantile group who come there from somewhere else and try to steal it from the locals.

Thus, the Na'avi have a righteous cause in the film...as is clearly recognized by some of the humans...and the mining company does not. Dead simple. It's not about "good" and "bad" people...or about "good" aliens and "bad" humans. It's about invasion, vandalism, and theft. If Earthlings were fighting a foreign invasion of the Earth, they'd be just as morally right as the Na'avi in Avatar.

And so we have films like "War of the Worlds". (which has still never been done as well as it could have been, and perhaps never will be)