As a reluctance to introduce body scanners at airports eases, two countries deploying them nationwide this month include Britain, reportedly a key setting for the Nigerian student's radicalization, and the Netherlands, where Mr. Abdulmutallab passed through undetected before boarding a flight to the United States.
But ardent opposition to them – including in the ranks of Europe's bureaucratic elite – may yet frustrate their international rollout. Beyond campaigners who worry about supposed health risks or view them as the digital equivalent of a strip search, many European aviation-security experts remain unconvinced of the cost benefits.
Frisking much less costly
"A thorough body frisk would do the same sort of thing, if it is done properly, and of course it costs a lot less," says Norman Shanks, a former head of security for the British Airports Authority, the United Kingdom's leading airport operator, who cautions that the technology is being viewed as a "panacea."
"Scanners also take up a lot of space. So, I hope that they will be used selectively, and restricted to a percentage of people. Otherwise, there will be long queues."
In the US, where around 40 machines are in use at 19 airports, the Transportation Security Administration (TSA) spent $25 million buying another 150 in September. Homeland Security Secretary Janet Napolitano said on Jan. 7 that there would be an "acceleration" involving the introduction of a further 300.
But a privacy group accused the TSA of misleading the public with claims that scanners would not store or send their graphic images. The Electronic Privacy Information Center produced TSA documents from 2008, obtained under a Freedom of Information Act lawsuit, in which the administration specifies that the scanners must have the ability to store and send images. The TSA responded by saying that this was for test purposes and the machines would be delivered without those capabilities.
Plans in Europe face more serious hurdles, not least the opposition of the European Commission's incoming justice commissioner. Passengers "must have the option of undergoing a body search," says Viviane Reding, who is to take up her powerful portfolio later this month. She could draft a law ruling out mandatory body scans at airports, but has stopped short of saying she will.
Privacy concerns have meant only a tentative embrace of scanners elsewhere in Europe. In Germany, officials said scanners would be considered once these concerns are resolved. Only certain airports will initially be equipped in France, where the idea of deploying them was dropped in 2008.
"The history of Europe is littered with totalitarian dictatorships, so in some ways there is greater sensitivity than in the US toward privacy, and weighing up data protection against national security," says Chris Pounder, a British data-protection expert. He believes that scanners can be made to comply with European laws by having protocols that ensure, for example, that operators viewing images cannot see the individual who has been scanned, and that images are deleted quickly.
Other takes on the privacy debate have also cropped up across the continent. The Rabbinical Center of Europe warned that scanners would violate the rights of religious Jewish women whose modesty would be compromised, while British children's rights campaigners said they could breach laws banning the creation of indecent images of children.
In a bid to address such worries, the Netherlands is testing software in scanners that displays a stylized body image – much like a stick figure – and highlights areas where objects are concealed.
Would machines have detected bomb?
A British Conservative MP who used to work for QinetiQ, a scanning technology firm, warned that scanners would probably not have detected the explosives reportedly strapped to Abdulmutallab's leg. "In all the testing that we undertook, it was unlikely that it would have picked up the current explosive devices being used by Al Qaeda," Ben Wallace said of passive millimeter wave scanners, attractive because of their low amounts of radiation.
Mr. Shanks, the former head of security at the British Airports Authority, also wonders about the future: "One wonders what would happen next time there was an incident with an individual who had concealed explosives internally."
One response is using transmission X-rays, which can see through the body. They are currently used only at some Russian airports to counter the threat from Chechen female suicide bombers.
Despite conforming to widely accepted safety standards, the X-rays emit higher levels of radiation. For now, the prospect of their introduction on a global scale appears distant, but experts have been quietly fretting about the next challenge to aviation since an Al Qaeda bomber with explosives inside his body tried to kill a Saudi prince last October.