WASHINGTON – A computerized system used by airlines to screen suspicious passengers failed to expose the 19 Arab hijackers on Sept. 11 because it omits key terrorist-profiling indicators such as national origin, a Federal Aviation Administration security official says.

If airlines had profiled based on human criteria, he says, the roughly 3,000 Americans who died that day might still be alive.

“If human-profiling was conducted on the terrorists who were made ‘selectees’ that day, then maybe some or all of this nefarious plot could have been avoided,” said the official, who works in the FAA’s Aviation Security Division here.

The Computer-Assisted Passenger Profiling System, or CAPPS, selected six hijackers for additional security screening on Sept. 11, because they bought one-way tickets using cash, things that show up as red flags in the system.

But only their checked luggage was searched, authorities say. The selected passengers themselves weren’t searched or even questioned by airport security personnel.

That’s because the so-called “Gore Commission” on aviation security last decade ruled out such profiling as discriminatory.

Washington-based Council on American-Islamic Relations lobbied hard against Arab-profiling at airports, enlisting lawmakers like Rep. David Bonior, a Democrat from a heavily Arab district in Michigan. He, in turn, lobbied FAA Administrator Jane Garvey. The airlines, which handled security at airport terminals, were also reluctant to profile Arabs.

“CAPPS was developed because the airline industry didn’t want to do human-profiling,” said the FAA official, who wished to remain anonymous. “Yet human-profiling is the single-biggest deterrent against terrorism in the aviation industry.”

CAPPS ignores key terror predictors, he says, such as the nationality, ethnicity, religion, language and even the sex of passengers. Young men of Middle Eastern origin tend to fit the anti-American or anti-Israeli terrorist profile, authorities say.

The computerized system instead flags passengers based on relatively sterile criteria involving the purchase of their tickets. Did they pay cash or credit? How many days in advance of the flight? One-way or round-trip? Are they irregular or frequent fliers?

Of course, such behavior can easily be changed by would-be hijackers to fool the system.

“CAPPS literally makes you a selectee based on how you purchase your ticket,” the FAA official said. “It has nothing to do with fighting terrorism, in spite of what the FAA says.”

The computer also selects a certain number of passengers by random.

For example, United Airlines Flight 93 passenger Nicole Miller was selected on Sept. 11 to have her checked bags secretly swept. The 21-year-old was heading back home to San Jose, Calif., where she went to college and worked as a waitress at Chili’s. Her hijacked plane crashed in Pennsylvania shortly after take-off from Newark, N.J.

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