If 23-year-old Umar Farouk Abdulmutallab had succeeded in his attempted Christmas day airline attack, 289 people would have died. But some security analysts say a powerful but controversial piece of technology might have prevented the alleged terrorist from ever boarding that Northwest Airlines flight to Detroit.
According to the Transportation Safety Administration, 19 airports across the country already give passengers the option to undergo a full-body imaging scan instead of a pat-down. And the agency recently purchased 150 more scanners that use X-ray beams to generate an image of a passenger -- including possible foreign objects hidden under their clothing.
In light of the recent attempted bombing, some security experts are raising their voices in support of a more widespread adoption.
Scanners Generate Full-Body Images of Passengers
"I value my privacy as much as any individual, but I travel all around the world, and when it comes to my safety and my family's safety, and I know these things work, then I want to be safe first and I'll worry about my body exposure later," said Billie Vincent, former director of the Federal Aviation Administration's Office of Civil Aviation Security and president of Aerospace Services International, Inc.
Full-body scans are generated by two kinds of technology. Millimeter wave scanners emit radio frequency energy to generate a 3-D image of a passenger. And backscatter scanners beam low-intensity X-rays to create a 2-D image.
Vincent said both scanners would have likely detected the foreign objects on Abdulmutallab's body.
The technology has been used in prisons and other military installations for years, but former Homeland Security Secretary Michael Chertoff told the Washington Post that it was time to renew calls for more widespread usage.
"This plot is an example of something we've known could exist in theory, and in order to be able to detect it, you've got to find some way of detecting things in parts of the body that aren't easy to get at," he said. "It's either pat-downs or imaging, or otherwise hoping that bad guys haven't figured it out, and I guess bad guys have figured it out."
Body Scanners Spot Threats Hidden Under Clothing
The imaging technology units range from approximately $130,000 to $170,000. The TSA purchased the 40-millimeter wave units currently in use from Santa Ana, Calif.'s L-3 Communications and the 150 new backscatter units from Torrance, Calif.-based Rapiscan Systems.
Even though the images can fuzz out parts of the body to protect a passenger's privacy, the technology is designed to spot metallic and non-metallic threats concealed under layers of clothing.
In a statement, a DHS spokesman said, "TSA is continuing to move forward with its current use and future deployments of imaging technology."
But the renewed interest in the scanners has also revived the critics, who say the scanners are a violation of privacy.
"I think the first question you have to ask is whether this actually works -- whether it works to protect our security," said Michael German, policy counsel for the American Civil Liberties Union. If not, he said, "This is an extreme loss of privacy without the security benefit."
On its Web site, the TSA says it has built "strict privacy safeguards" into its use of the advanced imaging technology. Officers who view the images never see the passengers being scanned and the images blur facial features. In addition, the units cannot store, print, transmit or save the images.
But German said "everything is in implementation."
"Human nature is you're curious and you're doing things you shouldn't do if there isn't strict oversight and accountability," he said. The powerful scanners can expose embarrassing medical equipment and prosthetics, he said, adding that electronic images can spread very quickly.
However, he added, if the manufacturers and the TSA can prove that the technology is effective, then he said it's important to discuss the methodologies that could best protect privacy.
Joe Reiss, vice president of marketing for American Science & Engineering, a Billerica, Mass. manufacturer of backscatter units, said "The backscatter X-ray gives the best detection capability of the widest array of threats."
His units are not used by the TSA but are used in prisons, border checkpoints and other military installations.
Former Airline Security Chief: People, Not Technology, Hold Keys to Safety
As for the privacy issue, he said that in pilot programs, 85 percent to 90 percent of passengers elect the scanner over the pat-down. On its Web site, the TSA says that more than 98 percent of passengers who encounter scanning technology during pilot programs prefer it over other screening options.
"To me, that's the answer to the privacy concern. They want to be protected. They don't want to worry about threats like Northwest Flight 253," Reiss said.
But others argue that when it comes to homeland security issues, funds are better spent elsewhere.
"Airport security is the last line of defense and not a very good one," said Bruce Schneier, a security technologist and author. "You pick a defense, [terrorists] look at it and then they pick an attack you haven't thought of."
He argued that it's "magical thinking" to attempt to thwart terrorist attacks by reacting to their last threats. Instead, he said, the government should boost investigation and intelligence efforts.
Isaac Yeffet, former head of security for the Israeli airline El Al, argued that people, not technology, hold the keys to enhanced public safety.
"The best security is not technology, the best security is a qualified and well-trained human being," he said.
Instead of deploying the revealing -- and potentially embarrassing -- full-body scans, Yeffet advocated for higher investments in airport security personnel.
He said security staff should be college grads, fluent in at least two languages and trained to authenticate travel documents and carefully question passengers about their travels.
"I want to make sure that when you talk to the passenger, you talk to every passenger and look them in the eyes," he said. "I have to ask all the questions. ... Through your answers, here I can determine if you are bona fide or suspicious."
Trained airport personnel can detect irregular body language and dubious explanations, but technology can't he said, adding, "I use technology to help me, not replace me."