When Mr Abdulmutallab failed to detonate his bomb last Christmas, for example, Mr Obama's Republican foes were quick to accuse the vacationing president of flaccidity in face of danger.

ECONOMIST: Lexington

Dianne Feinstein, D-California, Brennan confirmed a connection between al-Awlaki and Umar Farouk AbdulMutallab, who failed in his attempt to detonate an explosive in his underwear as his Northwest Airlines flight approached Detroit on Christmas Day in 2009.

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The attempt to ignite explosives hidden in AbdulMutallab's underwear failed to bring down the plane.

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The attack by Umar Farouk Abdulmutallab, a Nigerian, failed only because the explosives sewn into his underpants did not detonate fully.

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The question involved the handling of Umar Farouk AbdulMutallab, the suspect in the failed Christmas Day bombing of a U.S. airliner.

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But the official added, "One part of the system that absolutely failed" was that Abdulmutallab was able to board a plane to the United States allegedly with PETN.

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Luckily the bomb failed to detonate, although it set Abdulmutallab's clothes on fire.

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Despite that warning, Obama said, U.S. officials failed to "connect the dots" to prevent AbdulMutallab from boarding the flight.

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The cells appear to have little connection, but have provided ominous glimpses of what they may be capable of as in the failed airline attack involving the Nigerian, Mr. Abdulmutallab, and the three suicide bombings in July 2010 at restaurants in the Ugandan capital, Kampala, as patrons watched the World Cup soccer tournament.

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Part of the explosive device that failed to take down last week's flight from Amsterdam, Netherlands, was sewn into AbdulMutallab's underwear, authorities said.

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