A U.S. Marine with the 15th Marine Expeditionary Unit runs into position during a fire team movement rehearsal during Alligator Dagger at Arta Range, Djibouti, Dec. 15, 2017. Alligator Dagger, led by Naval Amphibious Force, Task Force 51/5th Marine Expeditionary Brigade, is a dedicated, bilateral combat rehearsal that combines U.S. and French forces to practice, rehearse and exercise integrated capabilities available to U.S. Central Command both afloat and ashore. (U.S. Air Force photo by Staff Sgt. Timothy Moore)

French service members run to get in position during a live-fire combat rehearsal as part of Alligator Dagger at Arta Range, Djibouti, Dec. 17, 2017. Alligator Dagger, led by Naval Amphibious Force, Task Force 51/5th Marine Expeditionary Brigade, is a dedicated, bilateral combat rehearsal that combines U.S. and French forces to practice, rehearse and exercise integrated capabilities available to U.S. Central Command both afloat and ashore. (U.S. Air Force photo by Staff Sgt. Timothy Moore)

A French service member checks his weapon in prepartion for a live-fire combat rehearsal during Alligator Dagger at Arta Range, Djibouti, Dec. 17, 2017. Alligator Dagger, led by Naval Amphibious Force, Task Force 51/5th Marine Expeditionary Brigade, is a dedicated, bilateral combat rehearsal that combines U.S. and French forces to practice, rehearse and exercise integrated capabilities available to U.S. Central Command both afloat and ashore. (U.S. Air Force photo by Staff Sgt. Timothy Moore)

A U.S. Marine machine gunner with the 15th Marine Expeditionary Unit overlooks a live-fire combat rehearsal during Alligator Dagger at Arta Range, Djibouti, Dec. 17, 2017. Alligator Dagger, led by Naval Amphibious Force, Task Force 51/5th Marine Expeditionary Brigade, is a dedicated, bilateral combat rehearsal that combines U.S. and French forces to practice, rehearse and exercise integrated capabilities available to U.S. Central Command both afloat and ashore. (U.S. Air Force photo by Staff Sgt. Timothy Moore)

U.S. Army Sgt. Jason Camp, a joint fires observer with 3rd Battalion, 144th Infantry Regiment, Texas National Guard, assigned to Task Force Bayonet, Combined Joint Task Force - Horn of Africa, communicates by radio as he overlooks the training site during Alligator Dagger at Arta Range, Djibouti, Dec. 17, 2017. Alligator Dagger, led by Naval Amphibious Force, Task Force 51/5th Marine Expeditionary Brigade, is a dedicated, bilateral combat rehearsal that combines U.S. and French forces to practice, rehearse and exercise integrated capabilities available to U.S. Central Command both afloat and ashore. (U.S. Air Force photo by Staff Sgt. Timothy Moore)

U.S. Army Soldiers with 3rd Battalion, 144th Infantry Regiment, assigned to Task Force Bayonet, Combined Joint Task Force - Horn of Africa, fire weapons at staged targets during a live-fire combat rehearsal as part of Alligator Dagger at Arta Range, Djibouti, Dec. 17, 2017. Alligator Dagger, led by Naval Amphibious Force, Task Force 51/5th Marine Expeditionary Brigade, is a dedicated, bilateral combat rehearsal that combines U.S. and French forces to practice, rehearse and exercise integrated capabilities available to U.S. Central Command both afloat and ashore. (U.S. Air Force photo by Staff Sgt. Allyson L. Manners)

U.S. Marines with the 15th Marine Expeditionary Unit take aim at a target during Alligator Dagger at Arta Range, Djibouti, Dec. 17, 2017. Alligator Dagger, led by Naval Amphibious Force, Task Force 51/5th Marine Expeditionary Brigade, is a dedicated, bilateral combat rehearsal that combines U.S. and French forces to practice, rehearse and exercise integrated capabilities available to U.S. Central Command both afloat and ashore. (U.S. Air National Guard photo by Staff Sgt. Allyson L. Manners)

U.S. Army Soldiers with 3rd Battalion, 144th Infantry Regiment, assigned to Task Force Bayonet, Combined Joint Task Force - Horn of Africa, fire a mortar as part of a live-fire combat rehearsal during Alligator Dagger at Arta Range, Djibouti, Dec. 17, 2017. Alligator Dagger, led by Naval Amphibious Force, Task Force 51/5th Marine Expeditionary Brigade, is a dedicated, bilateral combat rehearsal that combines U.S. and French forces to practice, rehearse and exercise integrated capabilities available to U.S. Central Command both afloat and ashore. (U.S. Air Force photo by Staff Sgt. Allyson L. Manners)

U.S. Army Soldiers with 3rd Battalion, 144th Infantry Regiment, assigned to Task Force Bayonet, Combined Joint Task Force - Horn of Africa, fire weapons at staged targets during a live-fire combat rehearsal as part of Alligator Dagger at Arta Range, Djibouti, Dec. 17, 2017. Alligator Dagger, led by Naval Amphibious Force, Task Force 51/5th Marine Expeditionary Brigade, is a dedicated, bilateral combat rehearsal that combines U.S. and French forces to practice, rehearse and exercise integrated capabilities available to U.S. Central Command both afloat and ashore. (U.S. Air Force photo by Staff Sgt. Allyson L. Manners)