An assault amphibious vehicle with 4th Assault Amphibian Battalion, 4th Marine Division, moves up toward a breached obstruction during the mechanized assault course of Integrated Training Exercise 4-19 at Marine Corps Air Ground Combat Center, Twentynine Palms, Calif., June 12, 2019. The ITX force includes each of the Marine Air-Ground Task Force’s subordinate elements who work together in the application of combined-arms maneuver warfare during the exercise. (U.S. Marine Corps photo by Master Sgt. Robert Brown)