U.S. Marines with 1st Battalion, 2nd Marines provide security for a platoon attack during Stand-in Force Exercise on Okinawa, Japan, Dec.11, 2022. SiF-EX is a Division-level exercise involving all elements of the Marine Air-Ground Task Force focused on strengthening multi-domain awareness, maneuver, and fires across a distributed maritime environment. This exercise serves as a rehearsal for rapidly projecting combat power in defense of allies and partners in the region. - U.S. Marines with 1st Battalion, 2nd Marines provide security for a platoon attack during Stand-in Force Exercise on Okinawa, Japan, Dec.11, 2022. SiF-EX is a Division-level exercise involving all elements of the Marine Air-Ground Task Force focused on strengthening multi-domain awareness, maneuver, and fires across a distributed maritime environment. This exercise serves as a rehearsal for rapidly projecting combat power in defense of allies and partners in the region.