A range of administration officials have stated that the threat of a major attack from Al Qaeda's main leadership in Pakistan has waned after Osama bin Laden's death in May, on top of the Central Intelligence Agency's increasing drone assaults on Qaeda targets in Pakistan's tribal areas over the past three years.
Mr. Brennan's assertions that the government only resorts to lethal force when "there is no other alternative" is at odds with reports of vastly increased drone strikes.
"You can't get through that bubble" to top foreign-policy officials, "penetrate that bubble and say, 'Do you understand what you're doing, both to American civil liberties and to the rest of the world's appreciation of America, with these increased drone strikes that seem to have an endless vista for future?'".
American officials have made veiled threats of increasing the drone strikes by the Central Intelligence Agency or conducting cross-border commando raids into Pakistan if the danger to American and allied forces in Afghanistan is not quelled.
According to McClatchy reporting, "a high-ranking Yemeni security official" says there was never anything to the supposed plot and that it was all "a misguided attempt at shifting public opinion in the face of increasing and unpopular American drone strikes".
Drones, wrote Richard Falk in an essay for Foreign Policy Journal, "seem destined to be central to operational planning for future military undertakings of the United States, with sharply escalating appropriations to support both the purchase of increasing numbers and varieties of drone".
More effectively is to increase the drone's fly height.
Since 2008, despite an almost four-fold increase of drone strikes, the U.S. claims to have simultaneously reduced civilian casualty rate from such strikes to around 1-21-2%
Mr Emmerson told journalists in London that the increasing use of drones "represents a real challenge to the framework of international law".
Obama has overseen increasing use of drones, in a targeted killing programme across the globe.
