Terrorist loophole: explosives under clothing at airport checkpoints.

• Author: Magnuson, Stew
• Position: HOMELAND DEFENSE

ATLANTIC CITY, N.J. -- On Dec. 22, 2001, passengers on a flight from Paris to Miami subdued Richard Reid after he attempted to bring down the airplane with a high-top sneaker filled with explosives.

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Ever since, travelers at airport checkpoints have been asked to take off their shoes and send them through x-ray machines.

Since the 9/11 hijackings, passengers have submitted to a variety of new Transportation Security Administration procedures, and some may have walked through the portals of a few new screening machines. However, the basic technology--metal detectors for the passengers and x-rays for the hand-carried baggage, has remained the same.

The relatively new TSA, meanwhile, has attempted to deploy cutting-edge sensors designed to both increase security and make the procedure smoother for passengers. Its efforts have been marked by notable failures, and few new technologies deployed uniformly throughout the United States. The problem of finding explosives concealed under clothing has not been completely solved.

"One of the hard lessons we've learned is that there is no single technology that is going to detect everything," Clark Kent Ervin, former DHS inspector general and now director of the Aspen Institute's homeland security program, said in an interview.

The United States is capable of developing the technologies needed to both boost security, and make the passenger screening procedure go faster, it just hasn't done so yet, Ervin said.

"Terrorists are on a quick timeline and we have got to be quick," he said. "We are capable of doing these kinds of things."

After 9/11, changes in TSA procedures have come in reaction to terrorist plots to detonate bombs aboard passenger aircraft. The actions of Reid, better known as the "shoe bomber," resulted in the footwear rule. A London-based plan to take down 10 aircraft in 2006 necessitated the banning of large quantities of liquids in hand-carried luggage. The so-called Christmas Day plot, which had Umar Farouk Abdulmutallab allegedly concealing plastic explosives in his underwear, prompted the TSA to dramatically boost the numbers of its new advanced imaging technology machines.

Abdulmutallab's attempt to destroy a Detroit-bound airliner highlighted the biggest vulnerability in passenger screening--the ability to detect explosives carefully hidden underneath clothing.

Scientists and engineers at the TSA Security Laboratory...