Last week's foiled airline bombing plot by a Nigerian man who hid explosives in his clothing has renewed debate in the United States as to how extensive and invasive passenger screening should be at U.S. airports. A few major airports already possess machines that can take detailed, full-body images, but Congress has not mandated widespread use of the technology.
Air travelers worldwide are accustomed to passing through metal detectors. But in an era of plastic explosives and advanced chemical compounds, that system has proved lacking.
Kip Hawley is a former head of the U.S. Transportation Security Administration, or TSA, which is charged with screening airline passengers and luggage.
"The number one area we need to focus on, the biggest potential vulnerability, is a bomb on the body," said Hawley.
Dutch officials have ordered detailed, full body scans of all U.S.-bound air travelers.
Terrorism expert M.J. Gohel of the London-based Asia Pacific Foundation applauds the move.
"These scanners are, in fact, very effective," he said. "They actually show a person's body - any foreign object attached anywhere in the body, even if it is internally. That kind of x-ray scanner would have located the package that this individual [Umar Farouk Abdulmutallab] had on the flight to Detroit. They are on a trial basis at the moment."
Fewer than two dozen U.S. airports possess full body scanners, which cost about $170,000 each. Earlier this year, the House of Representatives voted to prohibit widespread implementation of the technology for primary airline passenger screening.
A representative who co-sponsored the measure described body scans as a "virtual strip search" that the American public should not be subjected to, and suggested using explosives-sniffing dogs as a less-invasive method of detection.
The American Civil Liberties Union has said that full body scans amount to a "humiliating" assault on the dignity of passengers that citizens in a free nation should not have to tolerate.
But the ACLU's statement, like the congressional vote, occurred before last week's potential catastrophe on a U.S.-bound jet. President Barack Obama described the incident as a "systemic failure" of America's security apparatus, and U.S. officials have pledged to do what it takes to prevent a recurrence.
Former TSA Administrator Kip Hawley says Americans must weigh privacy concerns against the need for safe travel.
"We need to have a debate about how we feel about whole body imaging and the privacy trade-off, and it is a legitimate issue," said Hawley. "But it needs to be done in a security context as well."
Division over body scanning
U.S. air travelers this busy holiday season appear divided over whether they would want to submit to body scanning.
"I wouldn't want just anybody looking at me like that. It would be embarrassing, I think," said a woman.
"I would be objecting to that because at a certain point security begins to get into your personal life," said another one.
"I do not find it invasive," said the other one.
"Our security is important to me, and the security of the other people that are on the plane," said an air traveller. "So whatever needs to be done, needs to be done."
Experts warn that no matter what steps are taken to ensure safety, terrorists will adapt and craft new ways to defeat the security measures. But a high level of safety can be attained if the public is willing to endure significant inconveniences, according to former CIA analyst Michael Scheuer.
"You cannot build a foolproof system for air security unless you are willing to slow the whole air system down to a crawl and institute very, very invasive procedures before Americans get on airplanes," he said.
Most of the few U.S. airports that possess body scanning capability are using the technology for secondary screening of passengers who warrant closer examination by TSA officers. Whether the scanners are adopted more widely and how they are used, will likely be prime topics of discussion at congressional hearings expected early next year.