Mines, Naval. Underwater explosive devices are designed to sink ships, submarines, or other seaborne craft or by such threat to prevent them from using an area. Their firing mechanisms are either the traditional pressure points which detonate the explosive on contact or the modern influence devices which are triggered through magnetic or electronic sensors merely by the approach of a vessel. Most mines are automatic, but some harbor mines, controlled electrically by cable from shore, can be turned off to allow transit of friendly vessels. Moored mines are tethered to sinkers, and they float at predetermined depths generally to cut off particular areas. Traditionally they have been contact mines floating just below the water to damage surface ships that touch them, but more recently moored mines can serve as influence mines at depths of 3,000 feet or more against submarines. Ground or bottom mines are settled on the bottom in shallow waters such as rivers, harbors, and tidal areas to block their use, especially against amphibious invasion. In contrast to these stationary mines, a broad group of moving mines includes drifting and homing mines and deep‐water mobile and rising mines. Mines are small, relatively inexpensive, easily laid down, and require little maintenance. Yet they have the explosive ability to sink or badly damage even large vessels by blowing open their hull below the waterline. Consequently, smaller naval powers have often used them to impede the larger fleets of major powers.

Naval mines originated in the sixteenth century, but their use in naval combat began in the American Revolutionary War by David Bushnell, who placed such devices under the hulls of British ships in New York harbor using a small one‐man, wooden submarine he invented. During the Civil War, the Confederate Navy protected its harbors and sank a number of Union Navy ships using moored and mobile contact or electrically controlled mines (mislabeled “torpedoes”). Major use of underwater mines began in World War I with the British and later Americans planting tens of thousands of mines to contain the German surface and submarine fleets, and the Germans laying mines in British coastal waters. The Allies lost 586 ships and the Germans lost 150 warships and 40 submarines. In World War II, nearly 700,000 naval mines were laid, accounting for more ships sunk or damaged than any other weapon (the Allies lost 650 ships to mines, the Axis lost around 1,100).

Mining operations and countermining operations have been part of America's wars since World War II. Although the North Koreans did not use mines to try to prevent the Inchon Landing (1950), in the Korean War, they subsequently planted 3,500 Soviet magnetic mines at Wonsan, which took U.S. minesweepers a week to clear before the landing of United Nations forces there. In the Vietnam War, the U.S. Navy cleared mines so it could operate off the coast of North Vietnam, and in 1972 it mined Haiphong harbor, thereby blocking the influx of Soviet supplies. In the Persian Gulf War (1991), Iraq laid mines to block oil shipments and impede seaborne assault by the forces of the U.S.‐led coalition, but helicopter air sweeps, surface minesweeper ships, and underwater demolition teams cleared the sea lanes and access routes. Development of detection and countermeasures are becoming increasingly important since terrorists, such as those who planted mines in the Red Sea and the Persian Gulf in the 1980s, have begun to use this inexpensive stealthful weapon for its military, economic and considerable psychological effect.
[See also Anti‐Submarine Warfare Systems; Blockade; Mines, Land.]

Bibliography

Louis Gerken , Mine Warfare Technology, 1989;
Tamara Moser Melia , Damn the Torpedoes: A Short History of U.S. Naval Mine Countermeasures, 1777–1991, 1991;
Howard S. Levie , Mine Warfare at Sea, 1992;
Samuel Loring Morison , Guide to Naval Mine Warfare, 1995.

John Whiteclay Chambers II