I agree with you completely about the benefits of immigration to America. But AztlanIts is a potentially dangerous fantasy, since it prevents the beneficial assimilation which youre speaking of.
BTW, we have a park up in Wisconsin, Aztalan State Park the site of a Mississipian village thought to be related to the Aztecs.
Guess Wisconsin goes too. Madison would agree. ;>)
There was pressure on Polk to annex Mexico, and I believe a bill which passed the Senate, which was defeated in the House (too many new slave states), providing for annexation. Maybe some of the FR historians can help me on the facts of the legislation.
Would have been a very different continent.