If you feel so strongly about immigrants pretend they're Irish and post, "Irish Need Not Apply" and "No Irish" signs everywhere or be really brave and start a campaign to declare them "nonpersons" and murder them just like infants are routinely murdered.
They are when our economy and our social welfare systems are already collapsing and when the unemployment rate for Americans with comparable education levels to the illegals in question is 30.8% among all U.S. born citizens, 26.4% among U.S. born Hispanics, and 53.9% among U.S. born Blacks.
The principal of subsidiarity requires that we take care of our own first, before moving beyond our direct duties. No country can afford to provide welfare to the world. As another FReeper posted elsewhere, charity does not require self-destruction as part of the process.