Amphibious warfare is a military operation that is launched from the sea by naval and landing forces and involves a landing on a hostile shore.

Operations. An amphibious assault, the primary form of a combined sea-and-land operation, is conducted to establish a force ashore, usually to capture a beachhead as a necessary preliminary to further assaults ashore. The Normandy landings in World War II and the Inchon landing in the Korean War are examples of amphibious assaults that made second fronts possible and changed the strategic direction of the wars. In both instances, troops were ferried from warships by small, motorized landing craft that carried men and materiel through shallow water to the beaches.

Raids, demonstrations, and withdrawals are additional types of amphibious operations, each different from the assault in important ways.

In an amphibious raid the objective area is occupied only briefly, followed by a planned withdrawal. Such raids are conducted to damage the enemy, gain information, or carry out rescues. British commando raids in World War II, culminating in the Dieppe raid, were typical amphibious raids that depended on surprise and stealth for success. The U.S. freighter Mayaguez, captured by Cambodian Khmer Rouge guerrillas in 1975, was retaken in a lightning raid using amphibious forces.

An amphibious demonstration is a show of force that stops short of an actual landing. Demonstrations are conducted to deceive the enemy or, in situations short of hostilities, to signal presence and intent. During the Cuban Missile Crisis of 1962, large U.S. amphibious forces were conspicuously moved to the Caribbean, posing the threat of an invasion.

An amphibious withdrawal is essentially an amphibious assault conducted in reverse. The removal of Allied troops from Dunkerque, France, in World War II is often cited as the supreme example of an amphibious withdrawal. The evacuation of U.S.-South Korean forces from Hungnam in 1950, however, rivaled Dunkerque in scale and was much more successful, probably owing to uncontested U.S. air power.

Special Equipment. The slow massing of troops and equipment on a beachhead is a technique that can no longer be utilized in conflicts where rapid deployment is a necessity. Modern amphibious warfare must be fast and flexible. It uses all forms of troop transport, from helicopters to troop-carrying aircraft and landing craft. Planes, helicopters, and landing craft are carried aboard several different types of ship: amphibious command ships that serve as the control centers of combined land-sea-air operations; amphibious assault ships specialized in launching attack planes and helicopters; and transport docking ships, which also have docking wells for small landing craft.

The U.S. invasion of Grenada in 1983 centered on the U.S.S. Guam, an amphibious assault ship carrying Marines and Army Rangers, their artillery, and other equipment. Navy amphibious ships carrying Marines, amphibious tractors, and air-cushion landing craft spearheaded the sea/land assault on Kuwait's Iraqi invaders in the Persian Gulf War of 1991.

Brig. Gen. Edwin H. Simmons, USMC (Ret.)

Bibliography: Bartlett, Merrill L., Assault from the Sea (1983); Evans, M. H., Amphibious Operations (1990); Ladd, James D., Amphibious Warfare (1987); Moore, John, ed., Jane's Fighting Ships (annual); Simmons, Edwin H., The United States Marines, 1775–1975 (1976).