Vigilance.
CAMP NATHAN SMITH, Afghanistan – In the 2011 U.S. Army Photo of the Year, Pfc. Kevin March kneels atop a cliff overlooking the Arghandab River Valley to provide security for his squad as they climb up the cliff from the valley below in the Arghandab district, Afghanistan, Jan. 31, 2011. March is assigned to Company C, 1st Battalion, 66th Armored Regiment, 1st Brigade Combat Team, 4th Infantry Division.(Photo by Sgt. Breanne Pye, 1st BCT PAO, 4th Inf. Div.)