Keep in mind there are limitations, technologically and privacy-wise, to what we can do in screening PAX (i.e., we're not doing cavity searches)!

In the absence of such, a system that red-flags suspect persons and assigns them additional security (SSSS) or, perhaps, doesn't allow them to fly at all, may have some validity.

Also (switching gears here) I'm obviously not high up enough in the TSA food chain to be privy to any top-secret information. However, I've been around the agency long enough to have observed that it usually implements new measures and/or changes gradually, not revealing its end game during the process.

I think we're inevitably headed for some kind of registered traveler program that allows individuals who complete background checks to undergo less, or perhaps no, scrutiny at the checkpoint. But the key to making this work is the person who presents himself at the checkpoint MUST be the one with the clearance! Don't think that a potential terrorist wouldn't try to exploit this huge loophole.

Now, TSA administration isn't under any illusions as to the general capabilities of its screening staff -- it knows how many fail the relatively simple tests TSOs have to take annual to maintain certification! Therefore, it would make sense to have TSOs become practiced at checking I.D. using quite specific criteria before attempting to launch any such system.

Again, this is just a hunch, folks -- I guess we'll have to wait and see if it pans out!