and Ashley Halsey III

There are the lines, the scanners and the occasional need for a stranger to poke around in your luggage, but the No. 1 complaint passengers have with airport security is about removing their shoes.

Homeland Security Secretary Janet Napolitano said Tuesday that eventually that requirement will be dropped.

“You’re going to see better technology over time” that will detect shoe bombs without running the shoes through the X-ray machine, she said.

But Napolitano wasn’t able to say when new technology would come into use and she said restrictions on liquids are likely to continue.

Homeland Security Secretary Janet Napolitano said Tuesday that airline passengers eventually won’t be forced to remove their shoes when going through security. (JIM WATSON/AFP/GETTY IMAGES)

“In terms of what we see coming in the months and years ahead, it will probably be easier . . . to deal with the shoe issue before we can lift restrictions on liquids,” she said at a breakfast hosted by Politico.

Transportation Security Administration officials have said that passengers who register for a trusted traveler program they are developing may be allowed to skip the shoe screening sooner than the general public.

Napolitano said restrictions on liquids are likely to continue in part because intelligence reports suggest that terrorists are still trying to use nonmetallic detonation devices aboard commercial airliners operating in the United States and Europe.

Millions of passengers in the United States take off their shoes at airport security lines every week because of one act: Three months after the 2001 attacks, British-born Richard Reid tried to set off a bomb in his shoe on an American Airlines flight from Paris to Miami. A self-proclaimed al-Qaeda member, he was subdued by the crew and passengers.

There hasn’t been another shoe bomb attempt since, and aviation security experts question whether shoe removal is necessary.

“You don’t take your shoes off anywhere but in the U.S. — not in Israel, in Amsterdam, in London,” said Yossi Sheffi, an Israeli-born expert on risk analysis at the Massachusetts Institute of Technology. “We all know why we do it here, but this seems to be a make-everybody-feel-good thing rather than a necessity.”

John S. Pistole, the TSA administrator, cites a travel industry survey that found shoe removal was second only to the high price of tickets in passenger complaints. But he is unapologetic about the practice.

“We have had over 5.5 [billion] people travel since Richard Reid and there have been no shoe bombs because we have people take their shoes off,” Pistole said in an interview last month with Business Travel News.

But he recognizes the “hassle factor” and hopes that passengers who sign up for an upcoming trusted-traveler program will be exempted from some current security measures, including shoe removal. At some point, when technology is developed to ensure that everyone’s shoes are bomb-free, TSA expects to drop the shoe removal requirement.

Overall, however, Pistole has been moving the TSA toward a system that relies more on intelligence and passenger observation than technology.

That approach has been endorsed by independent experts on airline security.

“Richard Reid left a trail of suspicion with everybody who was in contact with him during the boarding process, yet Richard Reid was allowed to board an American Airline flight,” said Rafi Ron, former director of security at Ben-Gurion International Airport in Tel Aviv and now a security consultant in the United States.

Vahid Motevalli, head of the department of mechanical engineering technology at Purdue University, said that even though Reid’s attempt failed, it succeeded in adding a costly and frustrating layer of security.

“As a result of Reid, now everybody has to take their shoes off and we’ve added another expense,” Motevalli said. “These events create fears, disrupt lives and change the way you’re living. By that standard, that attempt was successful.”