"meaning it cannot be reasoned that they will detect bombers by random searches."
Hogwash.
If you profile, you increase the chances of finding someone with a bomb under their coat by a thousand fold. Once found with a bomb one, can easly reason that profiling and searches worked.
You apparently didn't read what I wrote. It is the RANDOM searches that are the problem.
Either search EVERYBODY or search all those who fit the profile/description. See my post #49.