Let's assume that 25 year old arab males are extremely bright (except, of course, for the self destruction part).

Because of their intelligence we are NEVER able to accunulate credible evidence prior to a bombing. Let's suppose that twice a month for the last 3 years a 25 year old arab male has been able to enter the country and blow them selves up in a US airport.

Lacking credible evidence on a future attack, would you agree that 25 year arab males might require extra scrutiny? If so, I believe that you would be accepting the concept of profiling.