The surge is underway, the war is funded, freedom is being furthered. Why clutter that rosy picture up with talk of benchmarks and timetables? The US military does not work that way - it's a laid back organization that doesn't deal well with structure and clearly defined goals. Note to Congress: Support the troops! Let them figure it out without getting all authoritarian about it.
Some people object, noting that a majority of Americans (and Iraqis too, as if anyone cared) want US forces to end their occupation of Iraq. American leaders should realize that "the will of the people" is often a euphemism for "mob mentality." The people in charge (if you have to ask, it isn't you) must resist the urge to listen to popular opinion and must instead consider the moral dimensions of the occupation.
The fact is, we have an ethical obligation to stay and complete the mission we started. Iraq cannot know freedom until its petroleum infrastructure is rebuilt and oil is back under $50 a barrel. Fortunately, the petroleum bill working its way through the Iraqi parliament is a good sign for us all.
Public opinion is fickle and loathe to consider the finer points and shades of grey of any issue. Responsible leaders will include strategic factors in the decision-making process - although they will often call them "moral factors".
When the United States starts a project, the world must know it can depend on the US to finish. Otherwise they'd start trying to share the spoils.