Papers, Please
One fact that I didn't bring up, but should have (and correctly brought up by Alpha Patriot) is the inevitability of a National ID card. Sure, they are only going to use it with illegal immigrants today, but before you know it, everybody will be required to have one.
Who knows, maybe they'll just combine it with your favorite credit card and put it into a Digital Angel chip, and implant it into your hand. With a barcode to show that you were implanted.
It does seem that the End Times are upon us.