M-1A1 Abrams Main Battle Tanks assigned to Delta Company, 2nd Tank Battalion, engage insurgents during an operation in Helmand province, Afghanistan, Sept. 9, 2013. The operation was a joint mission with Marines from 3rd Battalion, 4th Marine Regiment, 2nd Tank Battalion, and the Afghan National Army, 3rd Mobile Strike Force Kandak. (U.S. Marine Corps photo by Cpl. Trent A. Randolph/Released)