Afghan villagers gather on one side of a stream to watch U.S. and Afghan forces, on the other side, take a long halt while patrolling in the Shah Joy district of southern Afghanistan's Zabul province. With NATO strategy in Afghanistan now focused on protecting civilians, rather than killing the Taliban, the task of international troops and their Afghan government allies is to figure out how to bridge the gap and earn the trust of villagers like these.

As the war drags into its ninth year, and as President Barack Obama contemplates sending thousands more troops, Americans are fighting alongside Afghan government forces more closely than ever. But it’s an uneasy alliance.