Illegal immigration corrupts our ENTIRE legal system. You hve to create an entire class of laws that can be broken with impunity by a privileged class (of aliens no less). Laws that go by the wayside include: minimum wage, OHSHA, workers compensation, drivers license residence verification, identity theft (of SS numbers), moving vehicle violations (Mexicans with no identity or address simply don't show up to court), college residency requirements (see Arkansas), HUD home financing, the immigration laws themselves (including slavery, human trafficking and child worker laws), welfare qualifications, etc. etc.
Bush et. al. have no idea how terrible a path they have us on.
Cultural costs are almost never considered, either. The neighborhoods I mentioned almost always suffer from higher crime, vandalism, noise pollution and parking space congestion. Satellite dishes sprout like mushrooms in defiance of codes so illegals can remain insulated from English language and American customs. Signs become cluttered with Spanish reiterations where all preceding "immigrants" were fully expected to learn English.
I'd go on but I have to go look for an affordable apartment where I no longer have to deal with these atrocities on a daily basis.