Mission of the Marine Corps

The Marines are often referred to as the "Infantry of the Navy." Marines specialize in amphibious operations. In other words, their primary specialty is to assault, capture, and control "beach heads," which then provide a route to attack the enemy from almost any direction. The Marines were officially established on 10 November 1775 by the Continental Congress, to act as a landing force for the United States Navy. In 1798, however, Congress established the Marine Corps as a separate military service. The Marines are an elite fighting force. While amphibious operations are their primary specialty, in recent years, the Marines have expanded their equipment and training for other ground-combat operations, as well. The Marines are generally a "lighter" force when compared to the Army, so they can generally be deployed fast (although the Army has been making great strides in "rapid deployment" in the past few years). For combat operations, the Marines like to be self-sufficient, as much as possible, so they also have their own air power, consisting primarily of fighter and fighter/bomber aircraft and attack helicopters (that way, they don't have to ask the Air Force or Navy for air support). Even so, the Marines use the Navy for much of their logistical and administrative support. For example, there are no doctors, nurses, or enlisted medics in the Marine Corps. Those functions are handled by the Navy. Even medics that accompany the Marines into combat are specially-trained Navy medics. With the exception of the Coast Guard, the Marines are also the smallest service. There are approximately 18,000 officers and 153,000 enlisted personnel on active duty in the Marines. Like the Navy, there is no Marine Corps National Guard, but Marines are supported in times of need by the Marine Corps Reserves.
Fast Facts:

• The Marine Corps has more than 154,000 troops and more than 18,000 officers.
• A naval "Air Wing" will normally consists of one fighter squadron, three strike fighter squadrons, an Airborne Early Warning squadron, an Air Reconnaissance Squadron, an Air anti-submarine Squadron, a Helicopter Antisubmarine Squadron and an Electronic Warfare Squadron.
• The Marine Corps follow two parallel chains of command, one service and the other operational. The service chain begins with the president, through the secretary of defense, and continues through the secretary of the Navy and the commandant of the Marine Corps. The operational chain runs from the president, through the secretary of defense, directly to commanders of combatant commands.


• Commandant of the Marine Corps: The CMC reports to the Secretary of the Navy and is the top uniformed member of the Marine Corps. He sits on the Joint Chiefs of Staff and is responsible for the general readiness of the U.S. Marine Corps.

Officer Ranks

• General
• Lieutenant General
• Major General 
• Brigadier General
• Colonel 
• Lieutenant Colonel 
• Major 
• Captain
• First Lieutenant
• Second Lieutenant 

Marine Corps Organization

• Marine Expeditionary Force (MEF): The MEF is the principal war fighting element in the active force structure of the Marine Corps and is usually commanded by a lieutenant general. The size and composition of a deployed MEF varies depending on the needs of the mission.
• Marine Division: There are three Marine divisions in the active force and one in the reserve. It is the largest Marine ground combat organization of a MEF and is usually commanded by a major-general.
• Marine Expeditionary Brigade (MEB): A MEB, usually led by a brigadier general, is built around a reinforced infantry regiment, an aircraft group and a Service Support Group. Capable of rapid deployment and employment via amphibious or airlift methods, it is the first echelon of a Marine Expeditionary Force.
• Marine Expeditionary Unit (MEU): The smallest task force unit, the MEU has approximately 2,200 personnel and is built around a reinforced infantry battalion, a composite aircraft squadron and a support group. It is commanded by a colonel and is routinely deployed with an Amphibious Ready Group. The ground element of a MEU is a Battalion Landing Team (BLT), comprised of a reinforced infantry battalion of approximately 1,200 Marines, including three Rifle Companies. The aviation unit of a MEU is a reinforced medium helicopter squadron.
• Marine Air Wing (MAW): The largest Marine aviation organization of the MEF, each MAW has a unique organizational structure and is commanded by a brigadier general.
• Marine Aircraft Group (MAG): Similar to an Air Force Wing and commanded by a colonel, a MAG is the smallest aviation unit that is designed for independent operations.