William L. Eldridge, a Bataan Death March survivor, watches the opening ceremonies OF the 26th Annual Bataan Memorial Death March at White Sands Missile Range, N.M., on March 22, 2015. Eldridge was among the more than 60,000 prisoners of war, who endured the 60-mile long March in the Philippines April 1942. (Justin M. Boling/U.S. Marine Corps)

Sgt. Brenton A. Slover, squad leader, Engineer Platoon, Headquarters and Service Company, Ground Combat Element Integrated Task Force, observes the detonation of M1A2 Bangalores during a Marine Corps Operational Test and Evaluation Activity assessment at Range 107, Marine Corps Air Ground Combat Center Twentynine Palms, California, on March 22, 2015. (Paul S. Martinez/U.S. Marine Corps)

U.S. Marine Corps MV-22 Ospreys with Marine Medium Tiltrotor Squadron 262 (Reinforced), 31st Marine Expeditionary Unit (MEU), take off carrying noncombatant role-players during a Noncombatant Evacuation Operation as part of Certification Exercise, on Camp Hansen, Okinawa, Japan, March 22, 2015. (Ismael Pena/U.S. Marine Corps)

A U.S. Marine with Company L, Battalion Landing Team 3rd Battalion, 1st Marine Regiment, 15th Marine Expeditionary Unit, fast ropes in the hangar bay of the USS Essex during Composite Training Unit Exercise off the coast of San Diego on March 23, 2015. (Elize McKelvey/U.S. Marine Corps)

Marines with the 2nd Battalion, 6th Marines, acting as role-players, rush into a blockade of Marines as part of a riot-control exercise aboard Camp Lejeune, N.C., on March 24, 2015. (Kaitlyn Klein/U.S. Marine Corps)

The U.S. Marine Drum and Bugle Corps marches on during a Battle Color Ceremony at Liversedge Field, Camp Lejeune, N.C., on March 24, 2015. (Chris Stone/U.S. Marine Corps)

Cpl. Joshua J. Syverson, combat engineer, Engineer Platoon, Headquarters and Service Company, Ground Combat Element Integrated Task Force, carries a 155 mm shell during cache reduction as part of a Marine Corps Operational Test and Evaluation Activity assessment at Range 114, Marine Corps Air Ground Combat Center Twentynine Palms, California, on March 23, 2015. (Paul S. Martinez/U.S. Marine Corps)

U.S. Marine Lance Cpl. Andres Bravo loads onto an AAV-7A1 Assault Amphibious Vehicle before a mechanized raid as part Composite Training Unit Exerciseaboard the USS Rushmore off the coast of San Diego on March 24, 2015. (Emmanuel Ramos/U.S. Marine Corps)

U.S. Marines with the 24th Marine Expeditionary Unit, prepare to assault a simulated objective during Exercise Eagle Resolve 2015 at Failaka Island, Kuwait, March 24, 2015. (Devin Nichols/U.S. Marine Corps)

Smoke grenades thrown by course instructors envelop Marines with 2nd Battalion, 6th Marine Regiment, in thick, green smoke during a nonlethal weapons training exercise aboard Camp Lejeune, N.C., on March 25, 2015. (Fatmeh Saad/U.S. Marine Corps)