[jimthewiz]

I'm more concerned with the unnecessary searches conducted on obviously innocent passengers

Unfortunately there is no such thing as an obviously innocent person.
I think that a more practical approach would be concentrate the majority of the resources through profiling and the rest with random searches.
Maybe 80/20 would be a fair mix.

[yatros from flatwater]

Actually, the whole screening program is doomed by its swamping of predictive value. You cannot get any useful data from a test even if it is 99% accurate when you apply it to a sample of millions as is done in airport screening. Either you apply it only to "high-risk" subjects or not at all.

OTOH, if one really wanted to protect airplanes and passengers.......