U.S. spy agencies believe an American-born Muslim cleric based in Yemen played a bigger role than first thought in al Qaeda in the Arabian Peninsula's decision to start launching attacks on U.S. targets, counterterrorism officials said.
The revised assessment by intelligence analysts could help build a case for adding Anwar al-Awlaki to the U.S. target list to kill or capture top militants, though current and former officials said careful review was needed given his status as a U.S. citizen.
"It raises the bar dramatically," a former intelligence official said of authorizing the CIA or U.S. Special Operations forces to strike an American on foreign soil.
Other officials acknowledged the need for more scrutiny but said al-Awlaki could be added soon to the target list if a determination is made that he poses a direct security threat.
"The preferable course would always be a capture, but we are at war," the former official said. Pending a decision on whether the United States should target him directly, the former official added, "if we can do it through a third party, it's probably preferable."
Yemen has carried out air strikes with U.S. assistance targeting al Qaeda leaders, but there have been conflicting reports about whether al-Awlaki was present during any of those attacks. Officials believe he remains in hiding in Yemen.
U.S. intelligence agencies had viewed al-Awlaki as chiefly an al Qaeda sympathizer and recruiter for Islamist causes with possible ties to some of the Sept. 11, 2001, hijackers.
But that assessment started to change late last year with revelations about al-Awlaki's contacts with both the Nigerian suspect in the Dec. 25 attempted bombing of a U.S.-bound passenger jet and to the U.S. Army psychiatrist accused of killing 13 people at a military base in Texas on Nov. 5.
Al Qaeda in the Arabian Peninsula (AQAP) took responsibility for the attempted Christmas Day bombing of a flight from Amsterdam to Detroit.
The suspected bomber, Umar Farouk Abdulmutallab, has been cooperating with U.S. authorities, providing intelligence about the group, which purportedly supplied him with explosives that were sewn into his underwear, officials said.
"Awlaki is someone who has shifted his focus in recent years. At one time, he was principally a recruiter and propagandist. More recently, he's become a key player in terrorist operations - one who has helped turn AQAP's attention to planning attacks on U.S. interests," a U.S. counterterrorism official said.
Other U.S. counterterrorism officials described al-Awlaki as the main force behind AQAP's decision to transform itself from a regional threat into what U.S. spy agencies see as the network's most active affiliate outside Pakistan and Afghanistan.
Born in New Mexico, al-Awlaki was an imam at mosques in Denver, San Diego and Falls Church, Va. He returned to Yemen in 2004 where he taught at a university before he was arrested and imprisoned in 2006 for suspected links to al Qaeda and involvement in attacks.
Al-Awlaki, part of a prominent Yemeni family, was released in December 2007 because he said he had repented, according to a Yemeni security official. But he was later charged again on similar counts and went into hiding.
After Maj. Nidal Malik Hasan, an Army psychiatrist, went on a shooting rampage at the Fort Hood, Texas, base, U.S. authorities disclosed that he had been in frequent e-mail contact with al-Awlaki.
After the failed Christmas Day plot, U.S. and Yemeni officials said they learned that al-Awlaki had met with Mr. Abdulmutallab in Yemen.
In an interview with a Yemeni freelance journalist, posted on Al Jazeera television's Web site earlier this month, al-Awlaki described Mr. Abdulmutallab as "one of my students" but said he did not encourage the attack.