Sounds like some folks in this thread are suggesting that america institutes domestic passports. I think that is a really bad step for america and it's citizens -the soviets did this a long time ago to their citizens and there is absolutely nothing good that can come out of it.

In my travels i've seen domestic passports in third world countries used to oppress one group or another. This is not something that any democracy that cares for its citizens should do.

As someone else pointed out, looking at someone won't tell the truth either; how do you tell the difference between a palestinian and a israeli for instance? Or an american and a person from checnya? and the chechnyans are all muslims (remember beslan anyone?).

I think the idea of profiling based on ethnic origin is a bad one which seems to be advocated mostly by people who aren't in the class subjected to extra scrutiny.