We did vanquish the Taliban; our boys are doing grimy but excellent work keeping down terroristic sparks. As for keeping up appearances for political reasons - that is just one way to express what we are doing. Keeping the country pacified. It would require much more attention from the administration to do anything more than keep up appearances, and they have bigger fish to fry.
Our mission in the 'Stan is very simple: Keep the Taliban from coming back, keep Al Qaida from setting up any bases, and keep barbarians with bones in their noses and Quran on the brain from killing American or European office workers. Beyond that, if they want to sit around and daub themselves with animal droppings, I could give a flying hoot.