Profiling airline passengers is constitutional and effective

The error in that argument is that it is equally true of non-Arabs and non-Muslims, so why check anyone. TSA’s costly, cumbersome security apparatus is predicated on the belief that terrorists are trying to infiltrate airports. Accordingly, the relevant statistic is not the probability that a random Muslim traveler is a terrorist, which is, of course, small. Rather, it’s what statisticians call the conditional probability: Given that a terrorist is attempting to penetrate airport security, what is the probability that he is Muslim. That figure is much higher.

Since the 9/11 attack that spawned TSA, most, if not all, attempted airplane bombings have been perpetrated by individuals claiming to act in the name of Islam. This result is consistent with the suspect profile provided by bin Laden, who characterized would-be bombers as “soldiers of Allah.”

The objections from Islamic activists may not even represent broader Muslim opinion. Thanksgiving travelers largely ignored calls for a scanner boycott. In the same spirit, many Muslims may concede profiling is logical and submit to the relatively minor inconvenience of heightened screening in the interest of everyone’s safety including their own.

That said, perhaps Thanksgiving travelers should not have been so complacent about body scans. While the weight of the authority insists the technology is safe, it is unsettling that prominent experts remain unconvinced and believe more research is required. These include Dr. David Brenner, director of Columbia University’s Center for Radiological Research, who told NPR that there is “convincing evidence” that “there will be some cancers induced…by these X-ray devices.”

Scanners may not be the answer, but TSA cannot rely on religious profiling alone. A passenger’s religion is not always obvious. Even solid indicators like name and nationality might miss radicalized converts like shoe bomber Richard Reid who traveled under his English name. To account for such cases, profiling must be used in concert with existing screening protocols including random checks.

TSA has to decide whether it’s serious or not. If it is, it needs to break the taboo on profiling. Otherwise, it needs to stop annoying air travelers. As the president said in the context of the debate on stem cell research, decisions need to be based on “facts, not ideology.”

Daniel Huff is Director of the Legal Project at the Middle East Forum and a former counsel to the Senate Judiciary Committee.