A Marine rifleman holds security outside a simulated combat town after conducting a beach landing during Exercise Steel Knight aboard Marine Corps Base Camp Pendleton, Calif., Dec. 4, 2015. The U.S. Navy and Marine Corps continue to combine efforts to revitalize, refine and strengthen fundamental amphibious capabilities, and reinforce the Navy and Marine Corps team. Steel Knight will test the Marine Air Ground-Task Force's expeditionary capabilities through realistic, scenario-driven training. (U.S. Marine Corps photo by Sgt. Justin Boling)