Emma Sky, an Oxford graduate and Arabic speaker who became Petraeus' political adviser in Iraq, recalled that, "The biggest mindset change was for the U.S. to look at Iraqis as not the enemy, but to look at the Iraqis as people who needed protecting."

In February 2007 Petraeus was appointed by President George W. Bush as the new U.S. commander in Iraq just as 30,000 troops of "the surge" that Bush had recently ordered began arriving in Iraq.

Shortly after Petraeus' arrival he took a tour of Baghdad neighborhoods he knew from his past deployments. Petraeus later told me, "I just couldn't believe it...here's literally tumbleweed rolling down the street of what I remembered as a very prosperous, upper-middle-class, former military officers' neighborhood in northwest Baghdad. It was just. . .Wow!"

There were now well over 200 car bombings and suicide attacks every month in Iraq. Six months earlier there were around a quarter of that number. Iraq was simultaneously exploding and imploding.

Petraeus' new counterinsurgency approach got American soldiers out of their massive bases in Iraq and into Iraqi neighborhoods.

Petraeus explained this "population-centric" strategy in a letter he sent to all of the soldiers he commanded. "You can't commute to this fight...Living among the people is essential to securing them and defeating the insurgents...patrol on foot and engage the population. Situational awareness can only be guaranteed by interacting with people face-to-face, not separated by ballistic glass."

Emma Sky says that Petraeus played another key role, which was buying time in Washington for the new strategy to work by being the public face and advocate of the new approach in Iraq. "Without his strategic communications, without people's belief in Petraeus, we would never have got the time."

The greatest test of whether the political will existed to continue with the ramped-up Iraq effort were the congressional hearings held on the sixth anniversary of 9/11.

On September 11, 2007, Petraeus and Ryan Crocker, the veteran diplomat who was U.S. ambassador to Iraq, were grilled by both the Senate Foreign Relations and Armed Services committees, on which happened to sit five senators all seriously vying for the presidency-- Joe Biden, Christopher Dodd, Barack Obama, John McCain and Hillary Clinton--- one of whom would become president of the United States in just over a year.

Petraeus recalls that the hearing "Was just charged beyond belief. I mean, you could just feel the spotlight of the world on you. It was carried live in Baghdad."

Petraeus and Crocker gamely tried to present a picture of progress in Iraq, but the Democrats were having none of it. Clinton interjected at one point: "You have been made the de facto spokesman for what many of us believe to be a failed policy. Despite what I view as your rather extraordinary efforts in your testimony...I think that the reports that you provide to us really require the willing suspension of disbelief."

This is Washington-speak for you are either wrong or lying.

The day before, the duo had also testified before a joint hearing of the House Armed Services and Foreign Affairs committees. Petraeus knew it was going to be a rough day when he received a heads up that the New York Times was running a full-page ad about him, paid for by the left- wing advocacy group MoveOn.org.

Under a banner headline GENERAL PETRAEUS OR GENERAL BETRAY US?" the general was accused of "Cooking the books for the White House." The ad copy went on to assert, "Every independent report on the ground situation in Iraq shows that the surge strategy has failed...Most importantly, General Petraeus will not admit what everyone knows: Iraq is mired in an unwinnable religious civil war."

Despite these criticisms, Petraeus' cautiously worded congressional testimony about the turnaround that he was beginning to see in Iraq proved to be accurate.

The violence in Iraq, which was peaking in almost every category in the first months of 2007, steadily dropped after that. That decline was true across the board, including attacks by insurgents, civilian deaths, U.S. soldiers killed, Iraq security forces killed, car-bomb attacks and IED explosions.

In December 2006 the U.S. military map of "ethno-sectarian" violence in Baghdad was colored mostly yellow, orange and red, indicating medium to intense violence. The same map two years later was mostly colored green, indicating that the sectarian violence in Baghdad had largely subsided.

Of course, not all of this was due to the generalship of Petraeus. Other important factors such as the tribal revolt against al Qaeda's Iraqi affiliate worked in Petraeus' favor.

The Sunni Awakening movement had begun in 2006 before Petraeus arrived in Iraq, but he and his top commanders deftly managed it.

The tribal fighters of the Awakening movement ended up on the American payroll in the "Sons of Iraq" program, which by the spring of 2009 had grown to around 100,000 men. Many of those men had once been shooting at Americans; now they were shooting at al Qaeda.

Iraq today remains a dangerous place, but it is not in the grip of a civil war, and political differences are more likely to be decided by parliamentary maneuvers than by violence.

Certainly, Petraeus can claim a large share in the achievement of that outcome.

Petraeus was later tapped to try to turn around another war that wasn't going well, this time it was the war in Afghanistan and the call came from President Obama in 2010.

The jury is still out on what level of success Petraeus achieved during his tenure as the commander of U.S. and other NATO troops in Afghanistan.

As a result of the operations resulting from the "surge" of 30,000 U.S. troops into Afghanistan authorized by Obama and led in its latter stages by Petraeus, longtime Taliban havens in the southern Afghan provinces of Helmand and Kandahar have now been eliminated.