Always there is the illusion of the easy path. Always there is the illusion, which gripped Donald Rumsfeld and now grips many Democrats, that you can fight a counterinsurgency war with a light footprint, with cruise missiles, with special forces operations and unmanned drones. Always there is the illusion, deep in the bones of the Pentagon’s Old Guard, that you can fight a force like the Taliban by keeping your troops mostly in bases, and then sending them out in well-armored convoys to kill bad guys.

There is simply no historical record to support these illusions. The historical evidence suggests that these middling strategies just create a situation in which you have enough forces to assume responsibility for a conflict, but not enough to prevail…

A Taliban reconquest would also, it should be said, be a moral atrocity from which American self-respect would not soon recover.