You're entire theory is biased, baseless, and plainly ignorant.
The greater majority of the illegals are working on our farms, roads, yards, etc, allowing us to have far lower costs on these items, especially food. Its been proven in many studies that the net effect on US is positive.
Are there some bad in the bunch, of course, however, there are far more bad citizens that are a much higher concern than the really small number of illegals who are criminals. I live in Arizona which has, arguably, the worst situation with illegal immigration and more crossers die each year by a large number simply crossing the desert than they do committing crimes.
To remove the illegal issue would hurt us massively in dramatically increased produce far more than anything else. I like cheap tomatos and I know damn well no american will pick them in any way that wouldn't more than double their costs.
http://www.ehow.com/about_5389828_impact-immigration-economy.html
If I search long enough I could find the paper specific to CA where is proved a removal of immigrants would be severly detrimental to their economy.
