High Quality Content by WIKIPEDIA articles! The 31st Marine Expeditionary Unit (31st MEU) is one of seven Marine Expeditionary Units currently in existence in the United States Marine Corps. The Marine Expeditionary Unit is a Marine Air Ground Task Force with a strength of about 2,200 personnel. The MEU consists of a command element, a infantry battalion with artillery, amphibious vehicle and other attachments, a composite helicopter squadron reinforced with a Harrier squadron and a combat logistics battalion. The 31st MEU is currently based out of Camp Hansen, Marine Corps Base Camp Smedley D. Butler, Okinawa, Japan. This is the only permanently forward-deployed MEU, and is America`s expeditionary force-in-readiness in the Asia-Pacific region.