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 Ohio class of nuclear-powered submarines includes the United States Navy's 14 ballistic missile submarines (SSBNs) and its four cruise missile submarines (SSGNs). Each displacing 18,750 tons submerged, the Ohio-class boats are the largest submarines ever built for the U.S. Navy. They are also the third-largest submarines ever built, behind the Russian Navy's Soviet era 48,000-ton Typhoon class, the last of which was retired in 2023, and 24,000-ton Borei class. Capable of carrying 24 Trident II missiles apiece, the Ohio class are equipped with just as many missiles as, if not more than, either the Borei class (16) or the deactivated Typhoon class (20).
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).
The Lafayette class of submarine was an evolutionary development from the Ethan Allen class of fleet ballistic missile submarine, slightly larger and generally improved. This class, together with the George Washington, Ethan Allen, James Madison, and Benjamin Franklin classes, composed the "41 for Freedom," the Navy's primary contribution to the nuclear deterrent force through the late 1980s. The James Madison and Benjamin Franklin classes 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.
A cruise missile submarine is a submarine that carries and launches cruise missiles as its primary armament. Missiles greatly enhance a warship's ability to attack surface combatants and strike land targets; although torpedoes are a more discreet option for submerged submarines, missiles give a much longer stand-off range, shorter time to impact the target, as well as the ability to engage multiple targets on different headings at the same time. Many cruise missile submarines retain the capability to deploy nuclear warheads on their missiles, but they are considered distinct from ballistic missile submarines due to the substantial differences between the two weapons systems' flight characteristics; cruise missiles fly aerodynamically using flight surfaces like wings or fins, while a ballistic missile uses its engine power alone as it may exit the atmosphere.
A nuclear submarine is a submarine powered by a nuclear reactor, but not necessarily nuclear-armed. Nuclear submarines have considerable performance advantages over "conventional" submarines. Nuclear propulsion, being completely independent of air, frees the submarine from the need to surface frequently, as is necessary for conventional submarines. The large amount of power generated by a nuclear reactor allows nuclear submarines to operate at high speed for long periods, and the long interval between refuelings grants a virtually unlimited range, making the only limits on voyage times being factors such as the need to restock food or other consumables.
The Le Redoutable-class submarine was a ballistic missile submarine class of the French Navy. In French, the type is called Sous-marin Nucléaire Lanceur d'Engins (SNLE), literally "Missile-launching nuclear submarine". When commissioned, they constituted the strategic part of the naval component of the French nuclear triad, then called Force de frappe.
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.
USS Stonewall Jackson, a James Madison-class fleet ballistic missile submarine, was the third ship of the United States Navy to be named for Confederate States Army General Thomas J. "Stonewall" Jackson (1824–1863).a
There are three major types of submarines in the United States Navy: ballistic missile submarines, attack submarines, and cruise missile submarines. All submarines currently in the U.S. Navy are nuclear-powered. Ballistic missile submarines have a single strategic mission of carrying nuclear submarine-launched ballistic missiles. Attack submarines have several tactical missions, including sinking ships and subs, launching cruise missiles, and gathering intelligence. Cruise missile submarines perform many of the same missions as attack submarines, but with a focus on their ability to carry and launch larger quantities of cruise missiles than typical attack submarines.
HMS Churchill was the first of three Churchill-class nuclear fleet submarines that served with the Royal Navy.
United States Navy 
