Torpedo boats

A torpedo boat is a relatively small and fast naval ship designed to carry torpedoes into battle. The first designs rammed enemy ships with explosive spar torpedoes, and later designs launched self-propelled Whitehead torpedoes. They were created to counter battleships and other slow and heavily armed ships by using speed, agility, and the power of their torpedo weapons. A number of inexpensive torpedo boats attacking en masse could overwhelm a larger ship's ability to fight them off using its large but cumbersome guns. An inexpensive fleet of torpedo boats could pose a threat to much larger and more expensive fleets of capital ships, albeit only in the coastal areas to which their small size and limited fuel load restricted them.

The introduction of fast torpedo boats in the late 19th century was a serious concern to the era's naval strategists. In response, navies operating large ships introduced smaller ships to counter torpedo boats, mounting light quick-firing guns. These ships, which came to be called "torpedo boat destroyers" and later simply "destroyers," became larger and took on more roles, making torpedo attacks as well as defending against them, and eventually defending against submarines and aircraft. The destroyer eventually became the predominant type of surface warship in the guided missile age.

In the modern era, the old concept of a very small, fast, and cheap surface combatant with powerful offensive weapons is taken up by the "fast attack craft".

The American Civil War saw a number of innovations in naval warfare, including an early type of torpedo boat, armed with spar torpedoes. In 1861 President Lincoln instituted a naval blockade of Southern ports, which crippled the South's efforts to obtain war materials from abroad. The South also lacked the means to construct a naval fleet capable of taking on the Union Navy on even terms. One strategy to counter the blockade saw the development of torpedo boats, small fast boats designed to attack the larger capital ships of the blockading fleet as a form of asymmetrical warfare.

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