Lt. Col. Erick T. Clark, off-going commanding officer, 1st Battalion, 7th Marine Regiment, sits at the change of command ceremony for 1/7 aboard the Marine Corps Air Ground Combat Center, Twentynine Palms, Calif., June 4, 2018. 7th Marines where he relinquishes his command aboard the Marine Corps Air Ground Combat Center, Twentynine Palms, Calif., June 4, 2018. The change of command ceremony ensures that the unit and its Marines are never without official leadership, and also signifies an allegiance of Marines to their unit’s commander. (U.S. Marine Corps photo by Lance Cpl. Rachel K. Porter) - Lt. Col. Erick T. Clark, off-going commanding officer, 1st Battalion, 7th Marine Regiment, sits at the change of command ceremony for 1/7 aboard the Marine Corps Air Ground Combat Center, Twentynine Palms, Calif., June 4, 2018. 7th Marines where he relinquishes his command aboard the Marine Corps Air Ground Combat Center, Twentynine Palms, Calif., June 4, 2018. The change of command ceremony ensures that the unit and its Marines are never without official leadership, and also signifies an allegiance of Marines to their unit’s commander. (U.S. Marine Corps photo by Lance Cpl. Rachel K. Porter)