NO SINGLE technology can keep terrorists from boarding airplanes with bomb materials. That’s why expensive full-body scanners are not cure-alls for security breaches. It’s wise to expand the use of scanners, but only as part of a broader strategy to make flying safer.
Since the Christmas bombing attempt on a flight bound for Detroit, pundits and politicians alike have been clamoring for universal installation of full-body scanners at airports in the United States and abroad. It turns out the most vocal advocate for the scanners, former Homeland Security secretary Michael Chertoff, has a financial stake in their use: a company that makes the machines is a client of his consulting agency. The Transportation Security Administration has already announced that 150 scanners - in addition to the 40 already in use at 19 US airports - will be installed in airports across the country, including Boston’s Logan Airport, this year.
Full-body scanners give a more detailed view of what people are carrying under their clothes than current technology. But it’s debatable whether they would have detected the bomb materials hidden in the underwear of the man who tried to bomb Northwest Flight 253. Security experts are uncertain to what extent the scanner images - which the TSA has promised would be blurred over sensitive areas of the body to allay privacy concerns - would detect bomb materials in underclothing. Furthermore, the scanners cannot detect materials that would-be suicide bombers ingest or insert into their body cavities.
Airport security must be unpredictable enough that terrorists can’t adapt to it, and comprehensive enough that it can’t easily be breached. And no security measure can be better than the people carrying it out. Last week, a guard at Newark’s airport did not notice a man who walked across the security barrier. A General Accountability Office investigation in 2007 found that similar oversights are common. Aviation security strategy must reduce the potential for human error, while drawing on human intuition to detect threats. This requires better training and oversight of security officials, not just to consistently identify what shows up in scanners, but to notice people who sidestep security and to identify behaviors that suggest a terrorist motive.
Like drug trafficking rings, terrorist networks strive to be more nimble and adaptive than the government bureaucracies that aim to outsmart them. Upholding one technology as a panacea will not make flying safer. Ongoing adaptation of intelligence, interrogation, and technology will. As Winston Churchill said: “To improve is to change; to be perfect is have changed often.’’