MELISSA BLOCK, HOST:
Iraq is now a far more peaceful place than it was at the beginning of 2007. That's when President Bush sent 30,000 additional American troops there. The surge, as it was known, was widely seen as the turning point in the campaign to pacify Iraq.
But as NPR's Tom Bowman reports, one of the key players in that strategy now has a different take.
TOM BOWMAN, BYLINE: There are some iconic moments of the Iraq War. Pulling down Saddam Hussein's statue. Pulling Saddam himself out of a spider hole. And then there was the surge. It took on almost a mythic status for decreasing violence.
Here's General David Petraeus.
GENERAL DAVID PETRAEUS: The military objectives of The Surge are in large measure being met.
BOWMAN: Senator John McCain
SENATOR JOHN MCCAIN: The Surge is winning. Objective observers say the same thing.
BOWMAN: And Senator Lindsay Graham.
SENATOR LINDSEY GRAHAM: By every measure, The Surge of the troops into Iraq has worked.
(SOUNDBITE OF CHEERING AND APPLAUSE)
BOWMAN: Well, not everyone agrees.
DR. DOUG OLLIVANT: The Surge really didn't work, per se.
BOWMAN: That's Doug Ollivant. He was an Army planning officer in Baghdad, and took part in putting the surge troops on the street.
OLLIVANT: I think it was the Iraqis who essentially figured out their problems, used the Americans who were there to help them formulate that solution. Fundamentally, it was the Iraqis trying to find a solution and they did.
BOWMAN: Here's the conventional wisdom about the surge. By 2006, Iraq was in chaos. Many Americans called for the U.S. to get out. President Bush instead sent in 30,000 more troops, the surge. By the end of 2007 things started to stabilize.
Ollivant is now with a Washington think tank, the New America Foundation. He says what happened had less to do with the Americans and more to do with deep political and social forces inside Iraq. Ollivant's theory: Iraq's Sunni leadership realized it was losing a civil war to Iraq's larger Shiia population.
The Shiia were running the government. Shiia militias were wiping out entire Sunni neighborhoods and refugee camps.
OLLIVANT: So there was probably a very early signal to the Sunni leadership that this is not going well.
BOWMAN: So, Ollivant argues that the Iraqi Sunnis - who had been at war with the United States - decided to work with the Americans. And here's the key thing: They came to that conclusion before the surge.
So, Sunni leaders broke with their ally, al-Qaida, and helped the Americans target the terrorist group.
Here's Ollivant's take on the Sunni strategy.
OLLIVANT: The Americans then become our best friends because we've allied with them against al-Qaida, which is nominally the whole reason they're here in the first place. And they can help us cut a deal with the central Shiia government and get us the best deal out of this we can.
BOWMAN: Ollivant's bottom line is this: The American troop surge helped but the real change came from inside Iraq.
DR. KIM KAGAN: What Doug Ollivant's argument is putting forth is actually too simplistic a version.
BOWMAN: Kim Kagan wrote a book called, "The Surge: A Military History." She says Ollivant underestimates the role of American troops.
KAGAN: It does not look at the important dynamic between military change and increase in security.
BOWMAN: Kagan made many trips to Iraq at the height of the surge. She says Ollivant has it backwards, that it was the larger American military presence that convinced Sunnis to work with the Americans.
KAGAN: This is the fundamental dynamic of a counterinsurgency campaign, that first came security and then came change.
BOWMAN: So that's the question: which came first? Did more troops change Iraq? Or was Iraq already changing before more troops arrived?
John Nagl is a retired Army officer who helped write the Army counterinsurgency doctrine that guided the war in Iraq. He thinks Kagan has a point about the troops.
DR. JOHN NAGL: The 30,000 additional troops they used in a new way to provide more security inside Baghdad and in the rings around Baghdad, clearly played some role.
BOWMAN: But he says Ollivant is right to highlight the role played by Sunni and Shiia leaders to settle their differences.
NAGL: I think that mix coming together all contributed to a much more favorable outcome than we had any reason to expect.
BOWMAN: Bottom-line says Nagl: there were a number of factors at play. And it's hard to tell which was the most important.
NAGL: This is going to be a question that social scientists ponder for the next century.
BOWMAN: Doug Ollivant says it's important to learn the lessons of the Iraq surge, now that there's another surge, this time in Afghanistan.
Ollivant served as an advisor last year to senior U.S. officers in Afghanistan. And he says just like in Iraq, those American troops can only do so much to end the violence. In the end, he says, it's about the locals. Afghans are going to have to work out their differences if they want peace.
Tom Bowman, NPR News, Washington.