The government's effort to upgrade airport security over the past six months has been massive and expensive: federalizing airport security forces; confiscating toenail clippers; frisking randomly chosen grandmothers, members of Congress, former CIA directors, and decorated military officers; stationing National Guard troops in airports; putting sky marshals on planes. Has it been effective?

Not effective enough. The main reason is that civil libertarians, Arab-American activists, editorial writers, and most of polite society have virtuously eschewed the one measure—profiling based in part on national origin—that holds out the best hope of thwarting any skillful Al Qaeda terrorists who may try to smuggle bombs aboard airliners. More important, Transportation Secretary Norman Mineta has done the same in his public statements as of this writing, such as his assertion in a television interview aired on December 2 that 70-year-old white women should get the same scrutiny as young Muslim men.

Mineta is said to be considering the radical step of injecting some common sense into the profiling rules, if he has not done so already. (The detailed rules are secret.) He is expected to clarify his position in a speech on airport security set for March 15. But there has been no hint that he will depart from his previous suggestions (mirroring the rules he inherited from the Clinton Administration) that security screeners may pay no attention at all, ever, to the outwardly apparent traits—skin color, facial features, speech patterns, accents, names—that correlate with Middle Eastern origins. If that remains the rule, a passenger who looks and sounds just like Mohamed Atta, and who has, say, a Florida driver's license, will apparently not be targeted for individual searching unless he is too dense to avoid the various suspicious behaviors that trigger the profiling system. Those behaviors—paying cash, holding a one-way ticket, acting furtive, arriving recently from Pakistan, and the like—are not all that hard to avoid.

It's easy to understand the reluctance of Mineta and others to target passengers for individual searches based solely on how they look and sound. History gives us ample reasons to fear the slippery slope to which such profiling could lead. But the next Mohamed Atta may give us no other clue that would trigger an individual search. It's an agonizing dilemma.

I fear that a policy of ignoring apparent national origin and ethnicity may court disaster. And the social taboo against any approach that could be characterized (unfairly) as racial profiling has muzzled honest discussion of profiling, in the media and among politicians. Fewer than 10 percent of all checked bags go through any kind of bomb-detection machine, because we now have fewer than 200 of the more than 2,200 high-tech, minivan-sized bomb-detection machines that it would take to screen all bags. Only a small fraction of passengers and bags can be searched by hand without intolerable delays. The stopgap bag-matching system instituted earlier this year does not match bags to passengers on connecting flights and would have no effect on suicidal terrorists.

In short, as The New York Times reports, the "soothing veneer of security ... may be far thinner than many passengers imagine," and "no real progress has been made on bomb detection." What The Times won't tell you, lest it break the taboo, is that we might be able to make flying far safer almost overnight by using profiles that take account not only of suspicious behaviors, gender, and age, but also of the outwardly apparent traits shared by most militant Muslims from those regions where Al Qaeda finds most of its recruits—the very traits that the government's published rules tell security screeners to ignore. A well-designed profile that included such traits would properly be called "national-origin profiling," not "racial profiling." The main difference is that millions of Americans of Middle Eastern ethnicity would not fit the profile, because their speech patterns and travel documents would clearly indicate that they are long-standing residents of this country.

To be sure, a profile that takes account of apparent national origin (as well as one that does not) might miss a John Walker Lindh or a Timothy McVeigh. No profile is foolproof. But that doesn't justify being foolish. A well-designed profiling system would have singled out all 19 of the September 11 hijackers for special attention. And even though box cutters were not then prohibited on planes, security screeners might have wondered why groups of four and five Middle Eastern men were all carrying such potential weapons onto airliners the same morning.

The odds that any Middle Eastern passenger is a terrorist are, of course, tiny. But if you make the plausible assumptions that Al Qaeda terrorists are at least 100 times as likely to be from the Middle East as to be native-born Americans, and that fewer than 5 percent of all passengers on domestic flights are Middle Eastern men, it would follow that a randomly chosen Middle Eastern male passenger is roughly 2,000 times as likely to be an Al Qaeda terrorist as a randomly-chosen native-born American. It is crazy to ignore such odds.

While the politically correct approach to profiling still seems to be an article of faith in many quarters, some liberals (along with many conservatives) are talking sense. One is Rep. Barney Frank, D-Mass., perhaps the smartest civil libertarian in Congress. During a March 6 debate at Georgetown University Law Center, Frank forthrightly asserted that airline security profiles should take account of national origin. He cautioned that a well-designed profile would also include "a bunch of factors" that may warrant suspicion; that "if only ... young men from the Middle East were being profiled, it would be a problem"; and that the ideal system would be to search all passengers and their luggage thoroughly for bombs and other weapons. But Frank also stressed: "I do think that at this point, [national] origin would be part of it.... In certain countries, people are angrier at us than elsewhere."

Frank distinguished such airport profiling from the discredited police practice of "pulling over some black kid because he's driving," to search for drugs, which he called "a terrible intrusion." In airport screening, Frank said, the stakes are much higher—with many lives at risk if a bomb or weapon slips through—and the "incremental" intrusion on those profiled is minimal. "If no harm is being done, and you're not being in any way disadvantaged, I am reluctant to think that there's any great problem," he said.

The vacuousness of the arguments that have been made against politically incorrect profiling is typified by a recent Newsweek column by Anna Quindlen asserting that the case for "selective screening" based on ethnicity "collapsed amid reports that nine of the September 11 hijackers were indeed specially screened." That's about 180 degrees off. Those nine were apparently chosen based on their reservation-buying patterns, not ethnicity or national origin. And the screening appears to have been limited largely to searching checked bags: Arab-American activists and civil libertarians had prevailed on the government, not only to bar any profiling based on ethnicity, religion, or national origin in its Computer-Assisted Passenger Prescreening System, but also to avoid intrusive searches of the persons or carry-on bags of even those passengers who did fit the CAPPS profile.

Similar lobbying also succeeded in denying security screeners any access to law enforcement databases. That may help explain why the two hijackers who were on the CIA-FBI "watch list" of suspected terrorists were nonetheless able to board airliners with such ease on September 11. The new profiling system will include sharing of such intelligence. Good. But most Al Qaeda terrorists—including 17 of the September 11 hijackers—appear in no intelligence database.

"The most offensive profiles are those that are based on characteristics a person cannot change," including "race, religion, national origin, [and] gender," Katie Corrigan of the American Civil Liberties Union said in congressional testimony on February 27. But offensive or no, the only profiles likely to be effective against a well-trained terrorist are those triggered by traits that he cannot change or easily conceal. Corrigan added that profiling is a cheap, imperfect alternative to expensive security devices. She's right. But those security devices are not and will not be in place for many months, perhaps years. For now, intelligent profiling is indispensable.

The blessed absence of terrorist attacks on airliners since September 11 (excepting would-be shoe-bomber Richard Reid) appears to be fostering the complacent assumption that our security system works. The assumption is dubious. The politically correct approach to profiling amounts to a bet that Al Qaeda is no longer interested in airline terrorism. The bet is irrational.

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