I think that Afghanistan and Iraq are different battlefields and require different strategies. As Wretchard notes, Iraq is a more advanced state and it has oil. The stakeholders have a bigger incentive to find a peaceful equilibrium. Afghanistan and Northwestern Pakistan is far more tribal and parts of it rely on poppy as a cash crop.
Currently, I fear Afganistan/NW Pakistan far less than Iraq in 2006. It’s going to be a mess for a long time, but let’s face it, this is a very primitive enemy. A lot of it to me seems purely local warlording that we should stay away from. We should commit a sustain engagement to keep the Taliban and al Queda pinned down and slowly roll it back, but to expect a quick turnaround like the surge is unrealistic. I think any politician that emphasizes Afghanistan over Iraq is making a mistake. The biggest effort should be to make sure we win in Iraq and make sure the Pakistan nukes are never used. Iran is a different question.