> But, yes, most immigration was Europeans and African slaves but probably that was because it was expensive unless you effectively sold yourself.

You don't think it had anything to do with the Naturalization Act of 1790 that limited citizenship to whites, or the fact that even in 1965, congressmen felt the need to lie to the public and promise that law would not change US demographics? It was just because it was "expensive", that people from Europe immigrated, but not from South America?