Late to the thread but here are a few thoughts on the posts so far.
1) I work with a Chinese man who immigrated 20 years ago (legally). He's pissed. His point is less about the immigration and more about the demands of the illegal immigrants for benefits. I agree with him on this one - if you break the law then protest that I have to support you; it just doesn't seem right.
2) While there is racism against Mexicans, and other illegal immigrants there is also racism from them against Americans. Further, not all or even most that are concerned about this issue are racist.
3) Typically, economists would consider 4 - 5% unemployment as "full-employment". In short 4 - 5% of the population is incapable of work or anti-productive. Over the last decade, this country has been in good shape unemployment wise.
4) I believe that illegals do perform jobs that most Americans are unwilling to do at the current wages. To stop the flow completely would have pretty dramatic impacts on our economy.
Overall, I favor the Bush and Senate plan - control the borders, establish a guest worker program, use penalties for those already here if they want to enter the legit process.
While I have compassion for those here illegally in terms of seeking a better life and their family connections, I don't believe you can just break the law with no consequences. The arguments of this was originally Mexico are meaningless to me. Every piece of land was someone else's at some time. No one is entitled to come to this country but most are welcome to.