Riddle? What riddle?
Little known scientific fact:
The North American Continent was peopled by people from South America. Just because it was in prehistoric times does not mean there was not a government effort to end discrimination... and even then, the fossil record shows no government effort to control the borders.
Furthermore, Dr. Louis Farrakhan has informed me that those early undocumented migrants were originally from Africa.
Then they migrated to Africa and around the world.
That will supply an infinite number of dead Chicago democrats to vote and win every election.