WASHINGTON Newly retired General David Petraeus was sworn in as CIA director on Tuesday, taking over at a time when the line between the U.S. spy agency and the military has become increasingly blurred in the fight against Islamist militancy.
Petraeus, who in a storied 37-year Army career rose to become arguably the military's brightest star, took the oath of office from Vice President Joe Biden and then went straight into his first intelligence briefing with President Barack Obama.
"There is literally no time to waste. The president wants him on the job," Biden said at a brief White House ceremony.
Obama enlisted Petraeus to take over at the CIA as part of a major shuffle of his national security team that included Leon Panetta moving from CIA chief to defense secretary as successor to the retiring Robert Gates.
Petraeus was credited with helping to turn around the Iraq war and also set in motion Obama's revamped strategy in Afghanistan aimed at halting the momentum of Taliban insurgents and laying the groundwork for a gradual troop withdrawal.
Petraeus, 58, takes over at the CIA less than a week before the 10th anniversary of the September 11 attacks on New York and Washington that drew the United States into a protracted fight against al Qaeda and its Islamist allies.
Biden heaped praise on Petraeus, who was in a business suit for his first day as head of the civilian spy agency. "You have led and trained the 9/11 generation to become the greatest group of warriors this country has ever seen," Biden said.
Petraeus thanked Obama for an "extraordinary" opportunity.
But questions remain about how Petraeus will battle the perception of further "militarization" of the CIA and whether he will be able to deal objectively with agency analysts who take a less-rosy view of how well his much-vaunted counterinsurgency strategy has fared in Afghanistan.
His decision to retire from the Army, where he rose to the rank of four-star general, is meant to ease the transition.
As CIA chief, Petraeus is expected to embrace the agency's covert drone strikes in Pakistan, which have fueled anti-American sentiment there but have successfully struck at senior militants, including al Qaeda's No. 2 killed on August 22.
Petraeus's new role puts him in charge of handling delicate relations with Pakistani secret services, severely strained by the U.S. raid that killed Osama bin Laden in May.
Petraeus has dismissed concerns he would be unable to provide objective intelligence advice on the wars in Afghanistan and Iraq -- where the level of violence also remains high -- after leading those campaigns.
Known for mixing military know-how with political savvy, Petraeus was originally distrusted by the White House until he lowered his public profile as a top war commander.
His acceptance of the CIA post put an end to Washington speculation that he might be drafted by Republicans as a presidential or vice presidential candidate to challenge Obama and Biden in the 2012 election.
Petraeus, who has gained respect across party lines, easily won Senate confirmation in June.
Seeking to quell any concerns inside and outside of the CIA, Petraeus appears intent on fulfilling a pledge to leave his military "braintrusts" behind him as he settles into the CIA's Langley, Virginia, compound.
But it may be hard for Petraeus to divorce himself from a view shared at the highest levels of the U.S. military that the Afghan war is broadly trending in the right direction and that the Taliban's momentum has been reversed. The CIA has been more cautious in its assessment of the decade-old conflict.
Petraeus oversaw a "surge" of 30,000 extra U.S. forces that has focused on confronting the Taliban in their southern heartland. But despite gains on the ground, recent attacks have shown the Taliban-led insurgency is still far from quelled.
(Additional reporting by Phil Stewart and Mark Hosenball, editing by Mohammad Zargham and Eric Beech)