1st Battalion, 5th Marine Regiment

U.S. Marine Corps Staff Sgt. Shane Armstrong, an artillery cannon operator with 5th Battalion, 11th Marine Regiment, 1st Marine Division, checks a stack of M270 rockets during exercise Steel Knight (SK) 19 at Marine Corps Base Camp Pendleton, California, Dec. 7, 2018. SK19 is an annual training exercise and assesses the 1st Marine Division’s ability to conduct ground combat operations against a peer or near-peer adversary. The exercise challenges the division’s commanders, staff, and units in a dynamic scenario against a reactive and opposing force to refine the units’ command and control, interoperability, and fundamental warfighting skills. (U.S. Marine Corps photo by Cpl. Audrey M. C. Rampton)

A U.S. Marine Corps M142 High-mobility artillery rocket system fires a M270 rocket during exercise Steel Knight (SK) 19 at Army Facility Dugway Proving Ground, Utah, Dec. 7, 2018. SK19 is an annual training exercise and assesses the 1st Marine Division’s ability to conduct ground combat operations against a peer or near-peer adversary. The exercise challenges the division’s commanders, staff, and units in a dynamic scenario against a reactive and opposing force to refine the units’ command and control, interoperability, and fundamental warfighting skills. (U.S. Marine Corps photo by Cpl. Audrey M. C. Rampton)

U.S. Marine Corps Cpl. Ramon Trevino, an infantry Marine with 1st Battalion, 5th Marine Regiment, participates in a decontamination drill during Steel Knight 2019 (SK19) on Marine Corps Air Ground Combat Center, Twentynine Palms, Calif., Dec. 06, 2018. SK19 is an annual training exercise and assesses the 1st Marine Division’s ability to conduct ground combat operations against a peer or near-peer adversary. The exercise challenges the division’s commanders, staff, and units in a dynamic scenario against a reactive and opposing force to refine the units’ command and control, interoperability, and fundamental warfighting skills. (U.S. Marine Corps photo by Cpl. Rhita Daniel)

U.S. Marine Corps LCpl. Jeremy Yeager, a machine gunner with 1st Battalion, 5th Marine Regiment, participates in a simulated air assault during Steel Knight 2019 (SK19) on Marine Corps Air Ground Combat Center, Twentynine Palms, Calif., Dec. 05, 2018. SK19 is an annual training exercise and assesses the 1st Marine Division’s ability to conduct ground combat operations against a peer or near-peer adversary. The exercise challenges the division’s commanders, staff, and units in a dynamic scenario against a reactive and opposing force to refine the units’ command and control, interoperability, and fundamental warfighting skills. (U.S. Marine Corps photo by Cpl. Rhita Daniel)

U.S. Marines with 1st Battalion, 5th Marine Regiment, participate in a simulated air assault during Steel Knight 2019 (SK19) on Marine Corps Air Ground Combat Center, Twentynine Palms, Calif., Dec. 05, 2018. SK19 is an annual training exercise and assesses the 1st Marine Division’s ability to conduct ground combat operations against a peer or near-peer adversary. The exercise challenges the division’s commanders, staff, and units in a dynamic scenario against a reactive and opposing force to refine the units’ command and control, interoperability, and fundamental warfighting skills. (U.S. Marine Corps photo by Cpl. Rhita Daniel)

U.S. Marine Corps Cpl. Ramon Trevino, an infantry Marine with 1st Battalion, 5th Marine Regiment, participates in a training flight in preparation for Steel Knight 2019 on Marine Corps Base Camp Pendleton, Calif., Nov. 27, 2018. SK19 is an annual training exercise and assesses the 1st Marine Division’s ability to conduct ground combat operations against a peer or near-peer adversary. The exercise challenges the division’s commanders, staff, and units in a dynamic scenario against a reactive and opposing force to refine the units’ command and control, interoperability, and fundamental warfighting skills. (U.S. Marine Corps photo by Cpl. Rhita Daniel)

A U.S. Marine with the 1st Battalion, 5th Marine Regiment participates in a training flight in preparation for Steel Knight 2019 on Marine Corps Base Camp Pendleton, Nov. 27, 2018. SK19 is an annual training exercise and assesses the 1st marine Division’s ability to conduct ground combat operations against a peer or near-peer adversary. The exercise challenges the division’s commanders, staff, and units in a dynamic in a dynamic scenario against a reactive and thinking opposing force to refine the units’ command and control, interoperability, and fundamental warfighting skills. (U.S. Marine Corps photo by Cpl. Rhita Daniel)