Prometheus 6

The bigger challenge, however, may be enforcing such laws, if Arizona is any example.

Or maybe they are. 

Employers feel heat on immigration
Arizona's new law imposes sanctions – the stiffest in the US – for hiring illegal workers.
By Faye Bowers | Staff writer of The Christian Science Monitor

Phoenix

Arizona leads the nation in population growth. More illegal immigrants cross its border than any other in the United States. Now, in an apparent backlash to those trends, the state is leading the charge to halt illegal immigration by cracking down on employers.

Its new law effectively sets up a two-strikes penalty. A business employing an illegal immigrant would have its business license suspended temporarily. A second offense would mean a permanent revocation of that license.