Marine expeditionary unit

Marines loading on a Landing Craft Utility in 1999

The MEU is unique in that its air and ground combat elements are combined with a logistics combat element under one commander; other services do not unite the command of air and ground forces until much higher command levels.

The MEU's ground combat element also combines artillery, light armor, and tanks at a much lower level than was common in the Army until the development of the brigade combat team early in the War on Terror, with a similar concept, the combat command, being utilized in World War II.

This air-ground task force concept is designed to thoroughly exploit the combat power inherent in air and ground assets by closely integrating them into a single force. The MEU brings all the supplies and logistical support it needs to sustain itself for quick mission accomplishment or to prepare the way for follow-up forces. This self-sustainment allows more flexibility in disposition and operations of forces, and allows the MEU to initiate operations sooner and let support catch up later, without having to wait for external logistical support to begin a mission. Deployments on U.S. Navy amphibious assault ships allows MEUs to seabase around the globe, ready for deployment at short notice.

A typical MEU has approximately 2,200 members, including navy sailors. It is equipped with:

A UH-1N from the 26th Marine Expeditionary Unit flies past an AH-1W on the flight deck of USS Kearsarge

Many types of equipment are, or will soon, undergo a transitory phase as they are replaced. Some examples include the Amphibious Combat Vehicle replacing the AAV-7, the F-35 Lightning II replacing the AV-8B Harrier, and the CH-53K King Stallion replacing the CH-53E.

Recently, MEUs have been deployed within an expeditionary strike group (ESG) in the Mediterranean, the Western Pacific, and periodically, the Atlantic and Indian Oceans. An ESG is typically composed of three amphibious ships that embark the necessary troops and equipment and are escorted by a guided missile cruiser (CG) and guided missile destroyers (DDG) and submarine (SSN) support.

Before the ESG, MEUs were typically deployed as part of an amphibious ready group (ARG).

Marines with the 31st Marine Expeditionary Unit train from the amphibious transport dock ship USS Green Bay (LPD-20) in the Philippine Sea in 2022

MEUs maintain their subordinate elements in fifteen month cycles: nine months stateside (with six set aside for training), and a six-month deployment aboard ship. These cycles ensure that at least two of the seven MEUs are deployed forward at any given time.

Interim or buildup period: Upon completion of a deployment, the MEU remains "special operations capable" for approximately one month, prepared to respond to events around the world. They are not, however, considered a special operations unit by the Department of Defense. The MEU then releases its major subordinate elements (MSEs), retaining only its command element. This period provides the command element a chance to rotate select personnel and begin planning for the addition of newly assigned MSEs and “work-up” training. When the MSEs are received, the MEU begins six months of intense pre-deployment training.

Work-up period: Training during the six-month work-up period is often referred to as "crawl, walk, run". Marines and sailors progress through curriculum and exercises that teach individual, small unit, and unit tactics while integrating the separate MEU elements into a cohesive, flexible, and powerful force. The work-up period includes training in many combat and noncombat skills, to include:

• urban sniper
• mechanized and motorized raids
• non-combatant evacuation operations
• humanitarian assistance
• mass casualty
• scout swimmer
• jungle and/or mountain warfare
• riot control

Exercises conducted during the work-up period can include:

• Amphibious squadron—MEU integration training (PMINT)
• Realistic urban training exercise (RUT), formerly training in an urban environment exercise (TRUEX)
• Expeditionary strike group exercise (ESGEX)
• Special operations capable certification exercise (CERTEX or SOCCEX); prior to deployment, the MEU receives certification as special operations capable and then referred to as a "MEU(SOC)".

Deployment: Following the work-up period, the MEU deploys for six months in support of geographic combatant commanders. During this time, the MEU is a forward-deployed, self-sustaining force that combatant commanders can direct to accomplish a variety of special operations and conventional missions.

The missions may include:

• Conventional operations (amphibious assaults and raids)
• Tactical recovery of aircraft and personnel (TRAP)
• Humanitarian assistance operations (HAO)
• Noncombatant evacuation operations (NEO)
• Security operations.

• Marine expeditionary unit (special operations capable)
• Organization of the United States Marine Corps
• Regimental combat team

• Media related to Marine Expeditionary Units at Wikimedia Commons