Some more cheesy preparatory thoughts: I've been reading River-Horse by William Least Heat-Moon, about his trek across America by river. As he crosses Lake Oahe in South Dakota, he writes:

Considered truly for what they possess, the High Plains are as exotic as any oriental realm at the end of the Great Silk Road—their flora, fauna, and their native habitants whose ancestors learned to hunt and sing and chip flint points in Asia long before Great Walls, pagodas, or paddy fields. Those nomads out of Mongolia came in search of a Northeast Passage that led them into a new world where mammoths and mastodons died out and the horse and camel were born.

Of course, for all the nice sentiments there, even Least Heat-Moon's ideas might not fly with some of the locals. I was glancing through a book by Vine Deloria, Jr., an important Lakota writer and thinker, and he denies the "Bering Strait theory of migration," claiming that it is a result of "residual guilt . . . over the manner in which the Western Hemisphere was invaded and settled by Europeans."