I agree it's not effective, but what system, other than El Al's, is? I doubt that El Al's system could be implemented here because it's designed for a much smaller airline and air transportation system. My problem is with:

(1) the folks who resent any intrusion on their so-called freedom. For example, they feel the government has no right to check on what books/mags they've checked out at the local public library. They don't want the govt knowing they checked out a Chilton's Repair Manual for their '86 Plymouth Reliant, even if it means the govt won't know that Mohammed the Terrorist has checked out a book on how to grow botulism cultures at home.
It's this kind of mentality that prevented the Minneapolis FBI office from trying to get a search warrant for one of the 9/11 terrorist's laptops because they knew it wouldn't get approved. Who knows what the hard drive on that laptop might have revealed? The 3,000 9/11 victims sure won't.

(2) The politically correct idiots who prevent profiling. To them, a 20 year male from Saudi Arabia is just as likely to be a terrorist as a 90 year old grandmother in a wheelchair from Norway or a 7 year old little girl from New Zealand. Everyone is equal, don't you know? I read the other day that prior to 9/11 there was some FAA security reg that really punished airlines if they detained more than 2 Saudi nationals on any given flight. I'm sure the rich Saudis who bankroll the Arab terrorists did quite a bit of lobbying to get that gem implemented.