THE TENSION: Combat Camera: US Soldiers Clear Korengal Valley, Afghanistan

U.S. Army Spc. Andrew Harvey trudges across the steep cliff sides surrounding Korengal Valley, Afghanistan, during Operation Viper Shake, April 21, 2009. During the operation, soldiers from the 1st Infantry Division's Company C, 1st Battalion, 26th Infantry Regiment, hiked to elevations of more than 2,500 meters to disrupt violent extremists operating in one of Afghanistan’s most hostile areas. (U.S. Army photo by Sgt. Matthew C. Moeller.)

U.S. Army Spc. Andrew Harvey realizes he still has hours of climbing ahead as he stares up at the mountain peaks overlooking Afghanistan’s Korengal Valley during Operation Viper Shake, April 21, 2009. Harvey is an infantryman assigned to the 1st Infantry Division's Company C, 1st Battalion, 26th Infantry Regiment. (U.S. Army photo by Sgt. Matthew C. Moeller.)

U.S. soldiers establish a patrol base during Operation Viper Shake in the mountains surrounding Korengal Valley, Afghanistan, April 21, 2009. The troops are assigned to the1st Infantry Division's Company C, 1st Battalion, 26th Infantry Regiment. (U.S. Army photo by Sgt. Matthew C. Moeller.)

U.S. Army Cpl. Thomas Bourget watches over the mountains surrounding the Korengal Valley, Afghanistan, during Operation Viper Shake, April 21, 2009. Bourget is an infantryman assigned to the 1st Infantry Division's Company C, 1st Battalion, 26th Infantry Regiment. (U.S. Army photo by Sgt. Matthew C. Moeller.)

U.S. Army Pfc. Matthew Boyd checks the distance to the next objective during Operation Viper Shake in Korengal Valley, Afghanistan, April 21, 2009. Boyd is a forward observer assigned to the 1st Infantry Division's Company C, 1st Battalion, 26th Infantry Regiment. (U.S. Army photo by Sgt. Matthew C. Moeller.)

U.S. soldiers hike at elevations above 2,500 meters during Operation Viper Shake in Korengal Valley, Afghanistan, April 21, 2009. The soldiers are assigned to the 1st Infantry Division's Company C, 1st Battalion, 26th Infantry Regiment. (U.S. Army photo by Sgt. Matthew C. Moeller.)

U.S. soldiers plan their next movement during Operation Viper Shake in Korengal Valley, Afghanistan, April 21, 2009. The soldiers are assigned to the 1st Infantry Division's Company C, 1st Battalion, 26th Infantry Regiment. (U.S. Army photo by Sgt. Matthew C. Moeller.)