WASHINGTON (AP) -- Gen. David Petraeus is bidding farewell to the Army that has been his life and the troops that have been his family for 37 years.
America's best-known general is taking off his uniform before starting a new chapter as the 20th director of the CIA next week, where he will keep waging war on al-Qaida and other terrorist groups, but in a far different manner.
The soldier-scholar-statesman is to be sworn in as the nation's spy chief on Sept. 6, less than a week before the 10th anniversary of the terrorist attacks that killed nearly 3,000 people in New York, Washington and Pennsylvania.
It's a sharp and unexpected career turn for the man many thought would ultimately become the top officer in the land -- chairman of the Joint Chiefs of Staff -- after six command assignments, including four in war zones. He is credited with turning around the Iraq war and helping pivot the still uncertain campaign in Afghanistan.
Instead, President Barack Obama asked him to take over at CIA as part of a major shuffle of top national security officials that included Leon Panetta moving from CIA director to succeed the retiring Robert Gates as defense secretary.
Close friends and colleagues of Petraeus say that when he realized the White House would not make him chairman of the Joint Chiefs, he saw the CIA as the best alternative.
"I wanted this job," he told senators at his confirmation hearing, saying he had discussed the CIA post with the Obama administration for months.
Although he could have stayed in uniform at the CIA, Petraeus, 58, chose to shed it to avoid what some might see as the militarization of intelligence.
"I have a certain profile in various parts of the world," he told the Pentagon Channel in an interview Aug. 18. "And were I to travel there in uniform, it might create some confusion, frankly, as, you know: `Who is this guy? He's still in uniform. Is he the director of the CIA or is he actually something else?"'
Petraeus soared to public acclaim in 2007-08 with his surprising success in reversing an escalation of insurgent violence in Iraq.
At a September 2008 ceremony in Baghdad marking the end of Petraeus' 19 months in command, Gates credited him with dealing a "tremendous, if not mortal, blow" to an insurgency that two years earlier seemed beyond U.S. or Iraqi government control.
"I believe history will regard you as one of our nation's great battle captains," Gates told Petraeus.
Petraeus is credited with similarly solidifying gains against the Taliban in Afghanistan, though he himself says progress is "fragile and reversible."
Some critics of his push to add troops into the conflict there say Obama's decision to draw down those troops over the coming year shows the administration is abandoning Petraeus' counterinsurgency campaign.
Petraeus' aides disagree.
"That was the whole strategy from the beginning," to withdraw U.S. troops and replace them with Afghans, said Mark Jacobson, who just left the post as deputy NATO senior civilian representative in Afghanistan.
Petraeus also is seen as one of the Army's most accomplished accumulators of personal publicity. The Iraq war made him a household name. A July 2004 Newsweek magazine cover featuring Petraeus posing in front of a Black Hawk helicopter asked, "Can this man save Iraq?"
Petraeus is sometimes mentioned as a potential Republican presidential candidate, although he has said repeatedly he has no interest in politics.
His high public profile, following what most regarded as a successful first tour in Iraq in 2003, triggered some resentment in the Pentagon during Donald H. Rumsfeld's tenure as defense secretary. For that reason some saw his next assignment, to the Combined Arms Center at Fort Leavenworth, Kan., as a put-down.
"Various folks had said I've been sent to exile at Leavenworth," a bemused Petraeus told the Pentagon Channel.
But it was during that assignment in 2005-06 that Petraeus co-authored with Marine Gen. James Mattis an updated manual on how to fight a counterinsurgency campaign. It was a major success, and not just inside the military. Within a week of publication, the manual was downloaded 1.5 million times.
Petraeus put those ideas into practice when he was sent back to Baghdad as the top U.S. commander, arriving in February 2007 at a peak of sectarian violence and a low point of U.S. public confidence in the war.
He's fond of saying that the turnaround he and his troops achieved over the next year and a half was as much about a "surge of ideas" as the surge of extra troops that President George W. Bush ordered to Iraq in January 2007.
One of those ideas was to get American troops off their big, fortified bases and into small outposts throughout Baghdad, where they worked night and day with Iraqi forces to demonstrate U.S. resolve, build hope and confidence among ordinary Iraqis and gradually reverse the tide of violence. By most accounts, it worked, and Iraq grew stable enough for the Bush administration to negotiate in late 2008 an agreement to withdraw all American troops from Iraq by the end of 2011.
On the heels of that success, Bush made Petraeus commander of U.S. Central Command, overseeing all U.S. military operations in the greater Middle East, including Afghanistan and Pakistan. And when the top U.S. commander in Afghanistan, Gen. Stanley McChrystal, was abruptly relieved of duty in June 2010 for comments in a magazine story, Obama asked Petraeus to take over in Kabul and the general quickly agreed.
Petraeus grew up in a small town about seven miles from West Point, N.Y., and in 1970 he entered the U.S. Military Academy with the nickname "Peaches" and an ambition to become a doctor. He left with a commission as a second lieutenant and a commitment to a career in the infantry.
Shortly afterward he married the West Point superintendent's daughter, Holly Knowlton. His first overseas assignment was in Italy with a parachute infantry unit. In the 1980s he earned master's and doctorate degrees from Princeton University and taught international relations at West Point.
An errant bullet almost cut short his Army career in 1991. One of his soldiers accidentally shot him in the chest during an exercise at Fort Campbell, Ky. He recovered and went on to rise through the ranks in a series of assignments that included executive assistant to the chairman of the Joint Chiefs, Gen. Hugh Shelton, plus stints in Haiti and Bosnia. In 2003, as a two-star general, he took the storied 101st Airborne Division to Iraq.
He recalls the marching order he got from the Army's chief of staff, Gen. Peter Schoomaker, before heading to his Fort Leavenworth assignment in 2005.
"`Shake up the Army, Dave,"' the chief told him. "And we did our best."