United States Navy

==== Submarines ====
{{Main|Submarines in the United States Navy}}
[[File:USS Kentucky (SSBN-737).jpg|thumb|{{USS|Kentucky|SSBN-737|6}}, an {{sclass|Ohio|submarine|0}} [[ballistic missile submarine]]]]

The U.S. Navy operates three types of submarines: [[attack submarine]]s, [[ballistic missile submarine]]s and [[guided missile submarine]]s. All current and planned U.S. Navy submarines are nuclear-powered, as nuclear propulsion allows for a combination of stealth and long-duration, high-speed, sustained underwater movement.

Attack submarines typically operate as part of a [[carrier battle group]], while [[guided missile submarine]]s generally operate independently and carry larger quantities of cruise missiles. Both types have several tactical missions, including sinking ships and other subs, launching [[cruise missile]]s, gathering intelligence, and assisting in special operations. Ballistic missile submarines operate independently with only one mission: to carry and, if called upon, to launch the [[Trident nuclear missile]].

The Navy operates 69 submarines, 29 {{sclass|Los Angeles|submarine|4}} attack submarines (with two more in reserve), 18 {{sclass|Ohio|submarine|4}} submarines with 14 configured as ballistic missile submarines and four configured as guided missile submarines, three {{sclass|Seawolf|submarine|4}} attack submarines, and 19 {{sclass|Virginia|submarine|4}} attack submarines.