The resistance of many pundits to the notion that we just need to get the fuck out is due in part to their belief that We Must Be Able To Do Something. Things are fucked, and someone needs to fix the poblem. It's understandable that people gaze at a disaster, especially one of our own making, and imagine that there's something we can do to somehow make things better, but that doesn't mean that we can. More than that, our presence is a not insignificant part of the problem even if our absence won't cause the pony to appear.
We didn't have the ability to unshit the bed two years ago, and we don't have it now. More than that, this basic belief is part of what caused otherwise sensible people think we could fix things in Iraq in early '03.