Why not just destroy the Taliban and what we can find of AQ and leave? We could have continued every time either group stuck its head out, but without committing significant ground forces, or trying to turn Afghanistan into a democracy.
With respect, it sounds as if you're trading one untenable situation for another.

I don't find any comfort in a strategy that relies exclusively on our ability and willingness to react. I can think of no supreme benefit inherent in a stance where the enemy chooses the field of battle and weapons employed. Even the material benefit associated with opting out of an occupation is called into question when one realizes that much of our wealth is generated by the stability of our nation and its "infallible" image-- both sure to be damaged as the mosquito bites add up (or the mosquito manages to go NBC and provide us with a heavy dose of EEE).