United States Navy ships

Non-commissioned, primarily civilian-crewed vessels of the U.S. Navy under the Military Sealift Command have names that begin with USNS, standing for United States Naval Ship.

Modern cruisers, destroyers and frigates are called surface combatants and act mainly as escorts for aircraft carriers, amphibious assault ships, auxiliaries and civilian craft, but the largest ones have gained a land attack role through the use of cruise missiles and a population defense role through missile defense.

Aircraft carriers (CVN) have the ability to put most nations within striking distance of U.S. air power which makes them the cornerstone of US forward deployment and deterrence strategy.

Made up of both fixed-wing and rotary-wing aircraft, a carrier air wing is able to perform over 150 strike missions at once, hitting over 700 targets a day.

[6] Carrier air wings also protect friendly forces, conduct electronic warfare, assist in special operations, and carry out search and rescue missions.

The carriers themselves, in addition to enabling airborne operations, serve as command platforms for large battle groups or multinational task forces.

Expeditionary mobile bases are semi-submersible, flexible, modular platforms providing that perform large-scale logistics movements such as the transfer of vehicles and equipment from sea to shore.

By the early 20th century, cruisers could be placed on a consistent scale of warship size, smaller than a battleship but larger than a destroyer.

In 1922, the Washington Naval Treaty placed a formal limit on cruisers, which were defined as warships of up to 10,000 tons displacement carrying guns no larger than 8 inches in calibre.

In the later 20th century, the obsolescence of the battleship left the cruiser as the largest and most powerful surface combatant (excluding aircraft carriers).

The role of the cruiser varied according to ship and navy, often including air defense, commerce raiding, and shore bombardment.

Destroyers DDG are fast maneuverable long-endurance warships intended to escort larger vessels in a fleet, convoy or battle group and defend them against smaller powerful short-range attackers.

After the war, the advent of the guided missile allowed destroyers to take on the surface combatant roles previously filled by battleships and cruisers.

At the start of the 21st century, destroyers are the heaviest surface combatant ships in general use, with only two nations (United States and Russia) currently operating the heavier class cruisers, with no battleships or true battlecruisers remaining.

[13] On 30 April 2020, the US Navy awarded a contract to design and produce the next generation small surface combatant, the Guided Missile Frigate (FFG(X)).

It was "envisioned to be a networked, agile, stealthy surface combatant capable of defeating anti-access and asymmetric threats in the littorals."

Possessing lower air defense and surface warfare capabilities than destroyers, the LCS concept emphasizes speed, flexible mission modules and a shallow draft.

In December 2015, Secretary of Defense Ashton Carter ordered the Navy to reduce the planned LCS/FF procurement from 52 to 40, and downselect to one variant by FY 2019.

Using various mechanisms intended to counter the threat posed by naval mines, waterways are maintained clear for safe shipping.

Patrol ships PC are relatively small naval vessels generally designed for coastal defense duties.

They are commonly found engaged in various border protection roles, including anti-smuggling, anti-piracy, fisheries patrols, and immigration law enforcement.

"Attack submarines" (SSN) have tactical missions, including controlling naval and shipping activity, serving as cruise missile-launching platforms, and intelligence-gathering.