This is what we expect James Cameron will address in the sequel to Avatar and that is why we cringe when we see the movie. We were the tall, lean Natives looming over the bow legged refugees from the east. We were the ones who created an ecological paradise in much of the Americas, we lived at ease with the land, we took strength from our clans, we gave thanks for all things (including everything we consumed), we honoured the Great Tree of Peace, we held sacred the Great Tree of Light, we delighted in rituals and were, according to the Europeans, immodest in our dress. We, like the Na'vi, used tatoos, body paint and shaved our heads into the famous "Mohawk" hairstyle.
Given those similarities, which Mr. Cameron has acknowledged were by design, we can understand the Na'vi yet be apprehensive about their fate. Based on our experience the only way the Na'vi will survive is to act quickly and either form a confederacy of indigenous peoples in Pandora to (with a Tecumseh like leader) resist the Earthlings when they return or to convert all of Earth to the Na'vi way of thinking as would our prophet Skannenrahowi the Peacemaker.