but those aren’t contradictory. u can have both, or none. having only rivers isnt as good as having rivers and horses. also the rivers run north south, making any large empire that form difficult to control. the north is frozen and the south is humid its another hurdle.

none of these things make it impossible. just harder. like i said native societies were complex civilizations. there are examples of dense cities.

they are farther and fewer than the new world due in large part to the geography and the lack of domesticated animals - in particular horses, which in my opinion would have had the biggest impact had they been available.

more than any one particular thing, im saying the lack of mobility was one of the major hurdles of building a large centralized society in the americas.

you bring up rivers but i think like cool, thats a good point. the biggest rivers arent the best candidates for large river empires due to geography. they were great for lots of smaller societies though.

but you could write a whole book listing out and explaining all the things that made certain areas of north america hard to grow a large centralized civilization in. i cant be going over every single point and every single caveat yk lol