But in this document posted on the Web, a top al Qaeda commander writes: "The harm is alarming. The matter is very grave."
Both senior government officials and outside experts say it is an extraordinary confession, reports CBS News correspondent David Martin.
"It exposes for the first time a level of paranoia and a level of self-consciousness and a lack of confidence in al Qaeda's leadership in their propaganda that we just haven't seen up until now," said Nicholas Schmidle, the author of "To Live or to Perish Forever: Two Tumultuous Years in Pakistan."
In the past year, the CIA has flown more than 50 drone strikes in Pakistan, killing half of al Qaeda's top leaders and hundreds of its fighters. One senior official said the central leadership of al Qaeda is under more pressure now than at any time since the bombing of Tora Bora in 2001. The document blames the accuracy of the strikes on "spies … (who) have spread throughout the land like locusts … So many brave commanders have been snatched away … so many hidden homes have been leveled."
"The accuracy of these drone strikes has been so remarkable that there's been no - there's not even been an attempt to al Qaeda or the Taliban to offer a counter narrative to say that no there were actually women and children that were killed. There's been nothing but silence," said Schmidle.
The predator strikes do cause civilian casualties, but one senior official claimed more innocent people have been executed by al Qaeda as suspected spies than killed by CIA drones.