By sending a insufficient number of troops to occupy Iraq; by not ruthlessly incapacitating the opposition early on.
I didn't say the result would be acceptable.
What I said was the Democratically controlled Congress has made it a priority to get out of Iraq. With that as a given, there is absolutely no chance of a positive outcome.
With the errors made early on, there is in any case only a small chance of a positive outcome at this late date, 21k more troops notwithstanding.
So, no point in losing any more of our troops. Congress isn't going to support the Iraq operation. Period.