STEVE INSKEEP, host:
One of the most reliable defenders of the United States may be incompetence.
LINDA WERTHEIMER, host:
Terror plots are not easy to execute and several recent attackers made mistakes that foiled their efforts. There's no telling how many lives were saved, for example, when the Times Square attacker left behind a car bomb that failed to detonate.
INSKEEP: We've been looking this week at human error in terror plots and this morning we hear a warning that we may not always be able to count on it. Some groups are trying to eliminate human mistakes from the equation. Here's NPR's Dina Temple-Raston.
DINA TEMPLE-RASTON: This past fall, al-Qaida's arm in Yemen tried a new kind of attack: cargo bombs.
Unidentified Man #1: It's being described as the cargo plane bomb plot and it's sparked a global security alert.
Unidentified Man #2: Meanwhile, sources say there's no doubt the plot was hatched by al-Qaida in the Arabian Peninsula.
TEMPLE-RASTON: The details of that plot are familiar by now. There were two bombs wired up and hidden in computer printer toner cartridges. The bombs were put into boxes with clothing and other souvenirs from Yemen and then shipped to Chicago. That's what's been made public.
What intelligence officials are saying privately is that al-Qaida's arm in Yemen, the group that took responsibility for the attack, may have decided on cargo bombs for a very practical reason. After watching low-level operatives bungle attacks all year, the leadership may have been looking for ways to avoid rookie mistakes by directly managing plots themselves.
In this case, officials say, al-Qaida in Yemen's master bomb maker built the two bombs for the cargo plot and then AQAP just mailed them - no middlemen, fewer mistakes.
Mr. RICK NELSON (Center for Strategic and International Studies): One of the ways you can be more successful is by taking the human possibility of failure out of that chain.
TEMPLE-RASTON: Rick Nelson heads up the national security program at the Center for Strategic and International Studies.
Mr. NELSON: And I think that that's what you're seeing here, is individuals that they have hoped would conduct, you know, spectacular-like attacks that end up failing miserably. And so now they're going to continue to explore our vulnerabilities and probably try to identify ways that they can attack us but have it be much more successful.
Mr. PHILIP MUDD (Former Terrorism Official, CIA, FBI): I think they will look at ways to take humans out of the equation.
TEMPLE-RASTON: Philip Mudd is a former terrorism official with the CIA and FBI.
Mr. MUDD: I don't think that means that they'll stop trying to insert people into Western Europe or the United States.
TEMPLE-RASTON: Mudd says there's no reason to believe that terrorist groups can't do two things at once: try to get small-scale attacks off while lying in wait for an opportunity to do something bigger.
Mr. MUDD: A failure from our perspective is not a failure from their perspective. After all, on December 25th last year, and with the cargo attempts, they got tremendous international publicity.
TEMPLE-RASTON: While al-Qaida's arm in Yemen did manage to eliminate the human factor in the cargo plot, it still failed, but it was only because U.S. intelligence got a lucky tip.
Mr. MICHAEL CHERTOFF (Former Secretary, Department of Homeland Security): I'm Michael Chertoff. I'm a principal in the Chertoff Group, a security consulting firm, and I am the former secretary of Homeland Security
TEMPLE-RASTON: Chertoff says even though the cargo plot was foiled, it was still instructive.
Mr. CHERTOFF: Well, they learn by failing, frankly. I mean, the things that don't work, they improve.
TEMPLE-RASTON: And those improvements mean new and creative ways to attack.
Mr. CHERTOFF: And if you look, for example, at the airline liquid bomb plot in 2006...
TEMPLE-RASTON: The liquid bomb plot is the reason why you aren't allowed to carry shampoo or liquids in your carry-on.
Mr. CHERTOFF: ...that reflected the fact that we had raised the barriers to bringing on metal detonators. And so they looked for alternative ways.
TEMPLE-RASTON: Ways like liquid explosives, which could bypass the screening system.
Now, counterterrorism officials will tell you terrorists only need to get lucky once. Security officials have to be right every time. Philip Mudd says terrorists understand that too.
Mr. MUDD: I don't think we should interpret their efforts to learn as an effort to become perfect. They're just trying to get better, even while they'll accept losing people left and right in hopes that one out of 10 gets through.
TEMPLE-RASTON: Intelligence officials say they expect to be fending off smaller attacks next year as al-Qaida keeps trying to find cracks in the system.
Dina Temple-Raston, NPR News, New York. INSKEEP: It's MORNING EDITION from NPR News.
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