U.S. Marine forward observers attached from I Battery, 3rd Battalion, 14th Marine Regiment, 4th Marine Division, call for fire during the mechanized assault course during 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 Lance Cpl. Preston L. Morris)

U.S. Marine forward observers with I Battery, 3rd Battalion, 14th Marine Regiment, 4th Marine Division, and joint tactical air controllers with 4th Air Naval Gunfire Liaison Company, Force Headquarters Group call for fire at Observation Post Left during Integrated Training Exercise 4-19 at Marine Corps Air Ground Combat Center, Twentynine Palms, Calif., June 8, 2019. Marine Forces Reserve units participate in ITX to both complete annual training requirements and to increase unit readiness and proficiency. (U.S. Marine Corps photo by Lance Cpl. Preston L. Morris)

U.S. Marine forward observers with I Battery, 3rd Battalion, 14th Marine Regiment, 4th Marine Division, call for fire at Observation Post Left during Integrated Training Exercise 4-19 at Marine Corps Air Ground Combat Center, Twentynine Palms, Calif., June 8, 2019. Today’s Marine Reserve is a critical component of the Marine Corps’ Total Force, and training like ITX helps ensure Reserve units combat effectiveness and proficiency for world-wide deployment. (U.S. Marine Corps photo by Lance Cpl. Preston L. Morris)

U.S. Marine forward observers attached from I Battery, 3rd Battalion, 14th Marine Regiment, 4th Marine Division, call for fire during the mechanized assault course during 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 Lance Cpl. Preston L. Morris)