James Cameron has created the ultimate anti-American flick. The Marines killing off indigenous people just to get "Unobtainium" for ruthless and greedy capitalists. Come On.
Having said that, the film was lavishly produced and wonderfully imaginative. IMax put the critters, great and small, right in your lap. If you can ignore the genuinely hateful politics and don't require much of a plot, this is a rollicking good time. You'll also have to suspend reality, as it doesn't make any sense at all.