There were 18 Trident class submarines built for the US Navy between 1981 and 1997. The first of this class ‘Ohio’ was the largest submarine in the world at the time of entering service. One month later, the first of the larger Russian Typhoon class entered service. Each Trident submarine carries 24 Trident ballistic missiles that have a range of over 11,000 kilometers. These missiles have multiple warheads that can be directed onto individual targets. Although the Trident class submarines are also fitted with conventional 21-inch torpedoes, they are unlikely to be used, as they are capable of diving to 800 feet and with their super quiet propulsion system, their main aim is to stay undetected.

The eight Trident class submarines in the Pacific Fleet based at Bangor/Washington are Ohio, Michegan, Florida, Georgia, Henry M Jackson, Alabama, Alaska and Nevada. The ten in the Atlantic Fleet based at Kings Bay/Georgia are Tennessee, Pensylvania, West Virginia, Kentucky, Maryland, Nebraska, Rhode Island, Maine, Wyoming and Louisiana.

Ohio became the first Trident submarine strategic deterrent after setting out on her first deployment in October 1982. These submarines have a crew of around 170 and spend up to 70 days at sea on each deployment. In 1992, an agreement was reached at the Strategic Arms Treaty to cut the number of US Trident submarines to 14 by 2002. Rather than scrap four of these submarines, it is thought they will be converted to carry conventional missiles. Ohio was put into the navy yard at Puget Sound in 1993 to undergo a year long upgrade to her sonar, fire control and navigation systems.

The United States first submarine was the 53-foot long 75-ton Holland that entered service in 1898. The success of German submarines during the First World War proved how useful they could be to a modern navy. By the time World War Two had begun in 1939, the United States, Japan and Germany had built up large fleets of diesel-powered submarines. The US had around 200 submarines that served mainly in the Pacific War against Japan. They were credited with sinking 1,113 merchant ships and 214 naval vessels. Japans 174 submarines that took part in the war were credited with sinking 184 merchant ships and 14 warships. Germany operated over 1,000 submarines throughout the war. These submarines had their greatest successes attacking supply convoys traveling between America and Britain. The end of the war saw German submarines credited with sinking over 2,000 ships.