Paul Staniland is pessimistic:
Insurgencies can be militarily defeated, but at a high cost that may be greater than U.S. interests require. It is deeply doubtful that the U.S. should want to replicate in Afghanistan the experiences of counterinsurgency in Kashmir, Pakistani Baluchistan, or Sri Lanka. The Obama administration needs to decide if a similar strategy is worth the likely trail of American and Afghan blood.
A cheaper and more efficient policy for the United States in Afghanistan instead involves following the second pathway outlined above -- ugly stability. There is evidence that this approach has at least minimally succeeded in South Asia and Iraq. This strategy requires understanding and dealing with the real and existing social sources of power on the ground, mixing accommodation, coercion, and bribery, and being willing to accept imperfect and morally ambiguous outcomes. The U.S. may be able to satisfy its basic interests in Afghanistan without trying to build a simultaneously strong and legitimate central state.