we should leave when it makes sense for us to leave, and not one day sooner. when we are sure that IRAN will not try to subvert a legally empowered government in Iraq, well THEN we can leave...
There's no need for Iran to subvert anything... we seem to have allowed a very Iran-friendly constitution to be voted on. It made sense to have given them a constitution that made sense for our purposes last year, had them vote on it, and then left.
Unfortunately, the path we've chosen to take leaves us there indefinitely..