Optimistic comments from the Iranian foreign minister suggest that an accord with West may yet be reached.
Record U.S. fatalities there last month highlight the need for more troops, but reserves are few.
Even some military lawyers opposed the techniques, according to congressional testimony this week.
Officials want to ensure the change to a new administration goes smoothly.
Tuesday's deadly US incursion is under investigation, but it points up the contrast between the two nations' approaches to militants along the Afghanistan border.
Wednesday, a US airstrike killed 11 Pakistani soldiers near the Afghan border.
As Defense Secretary Robert Gates heads to Singapore, the Pentagon sees a turnaround in the Chinese security forces.
Taliban attacks are up, making this the worst season since the insurgency began and spurring greater Western troop deployments.
Democrats hope this week's hearings can shift the war's course. GOP wants Clinton, Obama to acknowledge its gains.
The latest, at a naval college in Lahore Tuesday, was the fourth in five days.