Absolutely !!!
However, I firmly believe that there are cells in this country made up of average-appearing Americans, much like John Walker and Richard Reid. I think that is why we have so many alerts, and why we haven't simply rounded up the Arabic types. It would do no good.
If I were a terrorist organization with lots of money, I would fund all sorts of fringe groups that could be prodded into wreaking havoc. I fiind it amazingly coincidental that the violence of PETA, ELF, and others has occurred during the last 6 years. I would almost bet cash money that bin Laden or his allies provide some of their funding.
So, profiling works in SOME cases. But that nice little granny that people feel sorry for may be carrying a bomb, unknowingly. What if her grandaughter married a guy from Yemen? What if her grandson is looking both to collect an inheritance and blow up a plane?
You see what I am thinking. I think we need to be suspicious of ACTIVITY, rather than individuals, not because I am PC, but because I think if we fall into the profiling trap we might get burned, big time.