A Marine Detachment, or MarDet, was a unit of 35 to 85 United States Marines aboard large warships including cruisers, battleships, and aircraft carriers. They were a regular component of a ship's company from the formation of the United States Marine Corps until 1998.[1] Missions of shipboard Marine Detachments evolved, and included protecting the ship's captain, security and defense of the ship, operating the brig, limited action ashore, securing nuclear weapons and ceremonial details. The Marines' successful command structure for dispersed detachments aboard warships encouraged detachments for other purposes.