Natural Progression

Where would Native Americans be today if left alone? That is, if the Americas were not colonized would the Native culture and religion be different then it is today? Obviously, if they still had the land to themselves, they wouldn't be living in reservations (which are often third-world poverty level) and there wouldn't be any hard feelings about the taking of their land. But as you look at the progression of the mound building of the native people, it seems interesting how it progressed from little mounds to bigger mounds, to huge mounds. it eventually became a way for them to send messages of dominance to other tribes; marking their land as their own. This is seen in the case of the village of Aztalan (Now a state park in Wisconsin:  http://dnr.wi.gov/org/land/parks/specific/aztalan/) where there are temple mounds and stockade fences around the village. The temple mounds are used to bury important people and to mark the land. This protective stance and land marking seems a far cry from the early mound builders, who simply buried the dead in small mounds (which are often barely even noticeable). I guess what I am getting at is that when I see that these tribes in the midwest became very protective and warlike, that contradicts my view of Native people as a peaceful people, and if the native people were left to progress without the interruption of the manifest destiny driven settlers would they have become even more like the (still manifest destiny driven) U.S. and other war loving countries? Or would there still be an emphasis on the natural world and simple living?