WASHINGTON -- The foiling of an al Qaeda plot to place an underwear bomber on a U.S.-bound airliner has focused attention on whether the more sophisticated device would have gotten past airport screening.
But security experts say the case also highlights the only surefire way to stop terrorism: a multi-layered approach led by good intelligence.
"Has any terrorist or terrorist-planted bomb ever been caught during screening inside an airport since 9/11?" a U.S. counterterrorism official who spoke on condition of anonymity said rhetorically when asked whether the Transportation Security Administration (TSA) could have thwarted the suicide bomber if the CIA had not.
"Good intel, kill or capture are infinitely more desirable actions for stopping would-be attackers than relying on airport screeners who hassle everybody, including people who hold classified clearances."
As the Associated Press first reported Monday, the unexploded bomb, which was stopped at its source in Yemen, would not have set off metal detectors because it was made of a non-metallic industrial explosive. The material, identified by several security experts as PETN, or pentaerythritol trinitrate, is the same explosive used in 2001 by "shoe bomber" Richard Reid and more recently by Umar Farouk Abdul Mutallab, the original "underwear bomber" who failed to detonate a similar device over Detroit on Christmas Day 2009. PETN also was planted inside printer cartridges shipped to the U.S. from Yemen on cargo planes in 2010.
Authorities suspect the new improvised explosive device (IED), which reportedly featured a more easy-to-use detonator, is the handiwork of master al Qaeda bomb-maker Ibrahim Hassan al-Asiri. His ability to get Mutallab and the cartridges on airplanes without setting off alarms led to a stepped-up effort to deploy Advanced Imaging Technology (AIT) body scanners at U.S. airports.
Former Secretary of Homeland Security Michael Chertoff said in an email to The Huffington Post that it is "too soon to tell how technically advanced [the] new device is. Imaging will pick up anomalies below clothing but [the U.S. government] has to analyze [the] device before adjusting protocols."
The body scanners, which use millimeter wave and backscatter technologies, can pick up bumps and lumps that older metal-detecting scanners can't.
According to the TSA, there are currently more than 670 AIT machines at about 170 U.S. airports. Major international airports in Canada, Britain and in Amsterdam have deployed body scanners and Australia plans to install them later this summer. But other European gateways, including major hubs in France and Germany, are not using them.
The machines, which were adjusted after complaints about "naked" airport scanners, are scarce outside the U.S. Health concerns prompted the European Union to ban backscatter versions at all European airports amid evidence their ionizing radiation can damage DNA and cause cancer. Body scanners are not used in Yemen or other countries considered high-risk incubators for terrorism, yet security experts say they are needed most in such originating locations -- not at U.S. airports that screen passengers and cargo.
"It's about pushing our borders out. We want to stop the threat as far away from our shores as possible, not stopping it at the water’s edge. Part of that 'away game' is trying to help international partners to have sufficient security at their own airports," said Chad Sweet, a Department of Homeland Security official who co-founded the Chertoff Group, a global security firm. "We’re only as good as the weakest link. We need collaboration with our partners."
A former CIA official familiar with the current investigation said it is impossible to be 100 percent certain an AIT body scanner would have detected the device had the would-be suicide bomber gotten as far as an airport. But he said the chances were good that the girdle-like device designed to be worn outside the body could have been caught. Citing information from a CIA source working with FBI bomb experts studying the device, the official said its powdery explosive was designed to be worn "compressed like a thin sheet of Play-Doh close to the skin" and high up near the groin in an area that would be beyond the scope of a pat-down.
"Body scanners are helpful but they aren’t everywhere, particularly overseas," wrote former TSA administrator Kip Hawley. "This means a pat down is urgently needed that is accepted by the public and consistently done properly by security officers of every culture in all locations."
Interviews with experts elicited few demands for better airport-checkpoint scanners in the wake of the latest plot. An aviation industry security expert who spoke on background said trace-detection equipment would "in all likelihood" have detected the underwear bomb. Others said random screening of passengers and carry-on bags or behavior detection techniques might have stopped the plot before boarding.
But Sweet said security can't be approached "myopically" when al Qaeda keeps developing new variations of IEDs to get around the latest TSA innovation.
"We have to get away from fighting the last war and get to the 'left of boom,'" he said, referring to the need to detect and disrupt plots using intelligence long before a bomb explodes. "It's like weeds -- you have to pull them up from the roots or they keep coming back. The jury is still out on whether we pulled this weed up by the roots. If they only got one suicide bomber and not network infrastructure, the root may still be there."
Rick "Ozzie" Nelson, director of the homeland security and counterterrorism program at the Center for Strategic and International Studies, a Washington think tank, agrees. "We face a very creative and adaptive enemy and we should expect them to continue to attempt such attacks, particularly ones aimed at the aviation industry," he said. "This demonstrates the strength of the counterterrorism apparatus that we've built over the last decade."
The former CIA official said statements like the ones from President Barack Obama's counterterrorism adviser John Brennan that the "device did not pose a threat to the American public" and White House spokesman Jay Carney that, "At no time were Americans in danger as a result of this," are strong evidence that the bomb may have been rendered inert before it was seized in the covert operation.
"Even if we lost track of the bomber, they had a degree of confidence it wouldn't work," the source said noting that the FBI has carried out numerous sting operations in which dummy explosives were substituted for the real thing. The arrest of a Moroccan immigrant who plotted to blow up the U.S. Capitol building is a recent example.
On Tuesday, Rep. Peter King, (R-N.Y.) said a weekend U.S. drone strike in Yemen that killed a senior al Qaeda leader accused in the 2000 bombing of the USS Cole was linked to the underwear plot. The operation indicates a more widespread effort to defang the terrorist group with the help of other countries, most noticeably Saudi Arabia and, according to the former CIA official, Israel's Mossad.
UPDATE: 5:11 p.m. -- DHS spokesman Matthew Chandler noted that the U.S. government does not conduct airport security screening overseas but "airports with direct flights to the United States are required to meet International Civil Aviation Organization (ICAO) security standards as well as additional measures required by TSA, including the use of AIT screening and other enhanced screening where available, pat downs and intelligence-based screening approaches. Following the attempted attack in 2009, DHS partnered with ICAO to issue a Declaration on Aviation Security, adopted by nearly 190 countries, which forged a historic new foundation for aviation security to better protect the entire global aviation system and make air travel safer and more secure than ever before."
"Aviation security is enhanced by utilizing multiple layers. Part of this layered approach is identifying threats to aviation security sooner, before they even get to the airport," he said, adding that DHS uses an array of passenger vetting capabilities prior to departure.
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