Submarine warfare

Submarine warfare is one of the four divisions of underwater warfare, the others being anti-submarine warfare, mine warfare and mine countermeasures.

Submarine warfare consists primarily of diesel and nuclear submarines using torpedoes, missiles or nuclear weapons, as well as advanced sensing equipment, to attack other submarines, ships, or land targets. Submarines may also be used for reconnaissance and landing of special forces as well as deterrence. In some navies they may be used for task force screening. The effectiveness of submarine warfare partly depends on the anti-submarine warfare carried out in response.

The age of submarine warfare began during the American Civil War. The 1860s was a time of many turning points in terms of how naval warfare was fought. Many new types of warships were being developed for use in the United States and Confederate States Navies. Submarine watercraft were among the newly created vessels. The first sinking of an enemy ship by a submarine occurred on 17 February 1864, when the Confederate submarine H.L. Hunley, a privateer sank the sloop USS Housatonic in Charleston Harbor, South Carolina. Shortly afterward, however, the Hunley sank, with the loss of her entire crew of eight. The crew was found later, on February 22.

Submarine warfare in World War I was primarily a fight between German and Austro-Hungarian U-boats and Atlantic supply convoys bound for the United Kingdom, France, and Russia. British and Allied submarines conducted widespread operations in the Baltic, North Sea, Atlantic, Mediterranean and Black Seas. Only a few actions occurred outside the wider European-Atlantic theatre. German submarine attacks on Allied merchant ships, especially the sinking of the Lusitania, turned American public opinion against the Central Powers and played a large role in the United States entering the war in April 1917.

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