The Benjamin Franklin class of US ballistic missile submarines were in service from the 1960s–2000s. The class was an evolutionary development from the earlier James Madison class of fleet ballistic missile submarine. Having quieter machinery and other improvements, it is considered a separate class. A subset of this class is the re-engineered 640 class starting with USS George C. Marshall. The primary difference was that they were built under the new SUBSAFE rules after the loss of USS Thresher, earlier boats of the class had to be retrofitted to meet SUBSAFE requirements. The Benjamin Franklin class, together with the George Washington, Ethan Allen, Lafayette, and James Madison classes, comprised the "41 for Freedom" that was the Navy's primary contribution to the nuclear deterrent force through the late 1980s. This class and the James Madison class are combined with the Lafayettes in some references.
The UGM-27 Polaris missile was a two-stage solid-fueled nuclear-armed submarine-launched ballistic missile (SLBM). As the United States Navy's first SLBM, it served from 1961 to 1980.
The UGM-73 Poseidon missile was the second US Navy nuclear-armed submarine-launched ballistic missile (SLBM) system, powered by a two-stage solid-fuel rocket. It succeeded the UGM-27 Polaris beginning in 1972, bringing major advances in warheads and accuracy. It was followed by Trident I in 1979, and Trident II in 1990.
A submarine-launched ballistic missile (SLBM) is a ballistic missile capable of being launched from submarines. Modern variants usually deliver multiple independently targetable reentry vehicles (MIRVs), each of which carries a nuclear warhead and allows a single launched missile to strike several targets. Submarine-launched ballistic missiles operate in a different way from submarine-launched cruise missiles.
A ballistic missile submarine is a submarine capable of deploying submarine-launched ballistic missiles (SLBMs) with nuclear warheads. These submarines became a major weapon system in the Cold War because of their nuclear deterrence capability. They can fire missiles thousands of kilometers from their targets, and acoustic quieting makes them difficult to detect, thus making them a survivable deterrent in the event of a first strike and a key element of the mutual assured destruction policy of nuclear deterrence. The deployment of ballistic missile submarines is dominated by the United States and Russia. Smaller numbers are in service with France, the United Kingdom, China and India; North Korea is also suspected to have an experimental submarine that is diesel-electric powered.
The George Washington class was a class of nuclear-powered ballistic missile submarines deployed by the United States Navy. George Washington, along with the later Ethan Allen, Lafayette, James Madison, and Benjamin Franklin classes, comprised the "41 for Freedom" group of submarines that represented the Navy's main contribution to the nuclear deterrent force through the late 1980s.
41 for Freedom refers to the US Navy Fleet Ballistic Missile (FBM) submarines from the George Washington, Ethan Allen, Lafayette, James Madison, and Benjamin Franklin classes. All of these submarines were commissioned 1959–1967, as the goal was to create a credible, survivable sea-based deterrent as quickly as possible. These submarines were nicknamed "41 for Freedom" once the goal of 41 nuclear-powered ballistic missile submarines (SSBNs) was established in the early 1960s. The 1972 SALT I Treaty limited the number of American submarine-launched ballistic missile tubes to 656, based on the total missile tubes of the forty-one submarines, in line with the treaty's goal of limiting strategic nuclear weapons to the number already existing.
The Ethan Allen class of fleet ballistic missile submarine was an evolutionary development from the George Washington class. The Ethan Allen, together with the George Washington, Lafayette, James Madison, and Benjamin Franklin classes comprised the "41 for Freedom" that were the Navy's main contribution to the nuclear deterrent force through the late 1980s.
USS Thomas A. Edison (SSBN-610), an Ethan Allen-class nuclear-powered ballistic missile submarine, was the second ship of the United States Navy to be named for the inventor Thomas Edison (1847–1931).
USS Lafayette (SSBN-616), the lead ship of her class of ballistic missile submarine, was the third ship of the United States Navy to be named to honor Gilbert du Motier, Marquis de Lafayette, a French military hero who fought alongside and significantly aided the Continental Army during the American Revolutionary War.
The James Madison class of submarine was an evolutionary development from the Lafayette class of fleet ballistic missile submarine. They were identical to the Lafayettes except for being initially designed to carry the Polaris A-3 missile instead of the earlier A-2. This class, together with the George Washington, Ethan Allen, Lafayette, and Benjamin Franklin classes, composed the "41 for Freedom" that was the Navy's primary contribution to the nuclear deterrent force through the late 1980s. This class and the Benjamin Franklin class are combined with the Lafayettes in some references.
USS Simon Bolivar (SSBN-641), a Benjamin Franklin class fleet ballistic missile submarine, was the only ship of the United States Navy to be named for Simón Bolívar (1783–1830), the Venezuelan hero of the independence movements of the former Spanish colonies in South America.
USS Lewis and Clark (SSBN-644), a Benjamin Franklin class ballistic missile submarine, was the first ship of the United States Navy to be named for the explorers Meriwether Lewis (1774–1809) and William Clark (1770–1838), who carried out the Lewis and Clark Expedition of 1804–06.
USS James K. Polk (SSBN-645), a Benjamin Franklin class fleet ballistic missile submarine, was the second ship of the United States Navy to be named for James K. Polk (1795–1849), the eleventh President of the United States (1845–1849). She was later converted into an attack submarine and redesignated SSN-645.
USS Daniel Webster (SSBN-626), a Lafayette-class ballistic missile submarine (FBM), was the only ship of the United States Navy to be named for Senator Daniel Webster.
USS Daniel Boone (SSBN-629), a James Madison-class ballistic missile submarine, was the only ship of the United States Navy to be named for Daniel Boone (1734–1820), the pioneer and frontiersman.
USS Casimir Pulaski (SSBN-633), a James Madison-class ballistic missile submarine, was the second ship of the United States Navy to be named for Casimir Pulaski (1745–1779), a Polish general who served in the American Revolutionary War.
USS Von Steuben (SSBN-632), a James Madison-class fleet ballistic missile submarine, was the second ship of the United States Navy to be named for Baron Friedrich Wilhelm von Steuben (1730–1794), a Prussian army officer who served in the American Revolutionary War.
USS Sam Rayburn (SSBN-635) was a James Madison-class fleet ballistic missile submarine named for Sam Rayburn (1882–1961), Speaker of the United States House of Representatives. Sam Rayburn was in commission 2 December 1964 to 31 July 1989 carrying the Polaris missile and later the Poseidon missile. Following decommissioning, ex-Sam Rayburn was converted into a moored training ship for use at the Naval Nuclear Prototype Training Unit at Goose Creek, South Carolina.
Submarine Squadron 15 is a squadron of submarines of the United States Navy based at Naval Base Guam.
United States Navy 
