An in-between option for Iraq?

In the discussions on whether the US should stay in Iraq or go home there is peculiar little attention given to the possibility of something in between, like getting out of the way while still hanging around in the neighborhood, close to the borders of Iraq, so as to see how it goes. Not only would this allow the Iraqis to take more ownership of their own destiny but also, if things go really haywire, for the US to return and help, something impossible if they have all gone home to Kansas. Any comment?