I read a recent analysis of Avatar [it seems the popular thing in some quarters] where people are offened by the movie for a variety of reasons, both on the left and the right. The criticism on the left deals with its treatment of indigenous cultures, and the need for a white savior. The criticism on the right deals with the bad guys being corporate imperialists, stereotypical businessmen and mercenaries using violence to rape the planet, kill the natives and make lots of money.
First, these may be worth thinking about, and the critiques may be on target. But anyone who describes their feelings about the movie as 'offensive' has serious problems. Lets save 'offensive' for things that are really disturbing, where great emotional pain is inflicted. Feigned offense, Michael Kinesley has pointed out, is a favorite political move to highlight something stupid someone else has said, but it allows people to avoid speaking about real issues.
Second, there is some truth to the criticism from the left, but it is easy to overstate, and misses some more important classic themes. The movie actually resembles quite a few movies and books over the past several centuries, with a common theme which has been called 'going native.' To truly appreciate this theme, you need to come from a racist or Eurocentric culture [we need a good word for the belief that one culture is superior to all others, similar to racism, but tied explicitly to culture instead of the quasi biological category of race.] And the culture of the heart of Europe in the 16-1900's fits the bill. On this view, native people are primitive, ignorant, savage and dumb, worthy only either of being used for the superior culture, being brought to the light of the superior culture, or of extermination. It is the backwards nature of the indigenous culture which then makes abusing its people, sometimes for their own good, justifiable.
Since the discovery of the Native American tribes, there was also a minority contrary view: some people discovered that the supposedly saveage and backwards culturee/people were not as backwards as thought by the majority, that the European [be it Dutch, English, French, Spanish, etc] culture has something perhaps to learn from the indigenous culture. And historically, some of these people were part of the military organization used to suppress the indigenous people. Only an Ameri-centric person would think this is talking about the US, though of course it applies to them, too. The English in India and other places, the Dutch in Indonesia, and the Americans in the Dakotas are all examples. At times, people in that setting leave not just their country, but their culture behind, and adopt the indigenous ways. This was common enough to get a name, derisive among the racist mainstream, 'going native.' An officer who went native was likely to be ostracized. After all, such a person would not do as commanded, would not support the imperialist nature of the regime he was defending, and mocked the supposed superioty of the home culture. Usually, such people were recalled, and replaced by someone more trustworthy.
In Holland, there was a novel made into a movie about just this type of person called 'Max Havilaar,' and, of course, in the States, this dynamic was portrayed in 'Dances with Wolves.' The theme is prominent in English writing about the Empire. 'Avatar' fits thus in a long line of such books and movies. In 'Avatar,' an American is able to physically embody an alien, and comes to understand the natives, then to appreciate the natives, then to become one of the natives. By exhibiting his transformation, we come to follow his footsteps. The reader, or viewer, too, comes to understand and appreciate the indigenous culture. We thus learn the lesson, as readers and viewers, that the notion of cultural superiority is problematic, and leads to great moral problems, as we can be asked to condone or to participate in the destruction of a worthy people/culture.
For this to work, you must have a person from the non-indigenous culture as the proponent. Following someone else's discovery of another culture allows us to discover it, too. And so while it may be odd to have the savior of the Navi be a white American, the anti-imperialist point could not really be conveyed in other ways.
And I will say this about the criticism of the right, that the movie makes capitalism the bad guy: hit a dog and it barks.