Marine Expeditionary Units (MEU) are designed as a quick reaction force to be deployed for immediate response to a crisis. Typically the units are around 2,200 troops in strength and are deployed from an amphibious assault ship.
A MEU might be deployed for any number of reasons, such as peacekeeping or humanitarian efforts, security operations, amphibious raids or assaults, or reconnaissance or surveillance. The men and women of these units must undergo a rigorous 26-week training program in order to be ready for any situation.
Several elements make up the MEU: ground combat element, aviation combat element, logistics combat element, and the command element. Additionally, many vehicles are involved – including battle tanks, light armored vehicles, amphibious assault vehicles, SuperCobra attack helicopters, Twin Huey utility helicopters, bulldozers, dump trucks, and high mobility multipurpose wheeled vehicles.
In recent times, MEUs have been deployed with an Expeditionary Strike Group (ESG) in various parts of the world. ESGs are generally composed of three amphibious ships (enough to carry the troops and equipment necessary) and are escorted by a guided missile cruiser, guided missile destroyers, and submarine support.