Fleet Ballistic Missile comprises a succession of nuclear-tipped missiles, initially with intermediate range (about 1,500 miles) but now with intercontinental range (about 5,000 miles) that is often called "the backbone of the nation's strategic deterrence."

Beginning in 1960 these missiles were aboard nuclear-powered U.S. submarines, able to cruise unseen in any ocean and to launch some or all at any time if so commanded by the President. There were initially 16 in each submarine but 24 at present. The first version was Polaris; later ones were Poseidon and now Trident.

Lockheed

Lockheed Corporation

The Lockheed Corporation was an American aerospace company. Lockheed was founded in 1912 and later merged with Martin Marietta to form Lockheed Martin in 1995.-Origins:...

 (now Lockheed Martin), FBM prime contractor since 1956, designed and built all of these missiles pursuant to initial design effort headed by Admiral Levering Smith and Lawrence Edwards

Lawrence Edwards

Lawrence K. Edwards is an accomplished American innovator in aerospace and ground transportation. Early in his career, he pioneered cutting-edge technologies for U.S. space and missile defense programs. He went on to invent and promote high-speed Gravity-Vacuum Transit and monobeam rail transit...

 of Lockheed. Electric Boat

Electric boat

While a significant majority of water vessels are powered by diesel engines, with sail power and gasoline engines also remaining popular, boats powered by electricity have been used for over 120 years. Electric boats were very popular from the 1880s until the 1920s, when the internal combustion...

 Company of General Dynamics

General Dynamics

General Dynamics Corporation is a U.S. defense conglomerate formed by mergers and divestitures, and as of 2008 it is the fifth largest defense contractor in the world. Its headquarters are in West Falls Church , unincorporated Fairfax County, Virginia, in the Falls Church area.The company has...

designed and built most of the nearly 100 submarines.