Sen. Barack Obama said it was "fair" to notice that he did not anticipate that the surge of U.S. troops into Iraq would be coincident with the so-called Sunni Awakening and the decisions of Shia militias to reduce their footprints, the combination of which led to measurable declines in violence.

In an interview with ABC's Terry Moran, Obama said that he "did not anticipate, and I think that this is a fair characterization, the convergence of not only the surge but the Sunni awakening in which a whole host of Sunni tribal leaders decided that they had had enough with Al Qaeda, in the Shii’a community the militias standing down to some degrees. So what you had is a combination of political factors inside of Iraq that then came right at the same time as terrific work by our troops. Had those political factors not occurred, I think that my assessment would have been correct."

Moran noted that Obama had claimed that the surge "would not make a significant dent in the violence."

Responded Obama: "In the violence in Iraq overall, right. So the point that I was making at the time was that the political dynamic was the driving force between that sectarian violence. And we could try to keep a lid on it, but if these underlining dynamic continued to bubble up and explode the way they were, then we would be in a difficult situation. I am glad that in fact those political dynamic shifted at the same time that our troops did outstanding work."

"But," asked Moran,"if the country had pursued your policy of withdrawing in the face of this horrific violence, what do you think Iraq would look like now?"

Obama said it would be hard to speculate. "The Sunnis might have made the same decisions at that time. The Shii’as might have made some similar decisions based on political calculation. There was ethnic cleansing in Baghdad that actually took the violence level down," he said.

Obama also told Moran that there were circumstances under which he could revise his instruction to U.S. generals to begin withdrawing combat brigades at the pace of one-to-two per month.

"I've always reserved the right, uh, to say---let's say that ethnic, uh, ethnic fighting broke out once again---I've reserved the right to say---I don't--I'm not going to stand idly by if genocide is occurring. I'm not going to stand idly by if vital United States interests are at stake. Um, so in that sense yes, I retain the flexibility anyone who in the job of commander in chief is constantly reassessing facts, risks, and so forth."

Read the full interview here.

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