“We are looking to draw on all of the capabilities at our disposal,” said a senior Obama administration official, who described plans for “a ramp-up over a period of months.”

The officials, who spoke on the condition of anonymity to discuss intelligence matters, stressed that that analysts continue to see al-Qaeda and its allies in the tribal areas of Pakistan as supremely dangerous adversaries. The officials insisted there would be no letup in their pursuit of Osama bin Laden and other senior figures thought to be hiding in Pakistan.

Indeed, officials said it was largely because al-Qaeda has been decimated by Predator strikes in Pakistan that the franchise in Yemen has emerged as a more potent threat. A CIA strike killed a group of al-Qaeda operatives in Yemen in 2002, but officials said the agency has not had that capability on the peninsula for several years.

“We see al-Qaeda as having suffered major losses, unable to replenish ranks and recover at a pace that would keep them on offense,” said a senior U.S. official familiar with the CIA’s assessments.