My current impression is that South American natives were much more developed technologically and govern-mentally than their North American counterparts. But I feel like I just have a few misconceptions.
Uh, the Aztecs are in North America. North America stops at Panama.
Unless you are talking about everything north of the Rio Grande, which is only part of North America. In that case I would point out examples like Chaco Canyon in the US Southwest or Cahokia near St. Louis which were large Native American cities.
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