The administration never even tried.
[Update a few minutes later]
Though I’ve noted it in the past, this is worth commenting on again:
He also undercut his own negotiating team by regularly bragging—in political speeches delivered while talks were ongoing—of his plans to “end” the “war in Iraq.” Even more damaging was his August decision to commit only 3,000 to 5,000 troops to a possible mission in Iraq post-2011. This was far below the number judged necessary by our military commanders. They had asked for nearly 20,000 personnel to carry out counterterrorist operations, support American diplomats, and provide training and support to the Iraqi security forces. That figure was whittled down by Defense Secretary Leon Panetta and Adm. Mike Mullen, chairman of the Joint Chiefs of Staff, to 10,000, which they judged to be the absolute minimum needed.
My emphasis. This is the standard rhetoric of the Democrats, and was very common throughout the war and particularly in the 2006 and 2008 campaigns. Their only solution to wars is to “end” them — we are never allowed to actually win one by the left, or even consider the possibility, and haven’t been since World War II.