Updated September 19, 2019 Defense Primer: Naval Forces “Naval Forces” Refers to Both the Navy and Marine Corps Although the term “naval forces” is often used to refer specifically to Navy forces, it more properly refers to both Navy and Marine Corps forces, because both the Navy and Marine Corps are naval services. For further discussion, see “Defense Primer: Department of the Navy.” For a discussion of the Marine Corps that focuses on its operations as a ground-combat force, see “Defense Primer: Ground Forces.” U.S. Strategy and Naval Forces U.S. naval forces give the United States the ability to convert the world’s oceans—a global commons that covers more than two-thirds of the planet’s surface—into a medium of maneuver and operations for projecting U.S. power ashore and otherwise defending U.S. interests around the world. The ability to use the world’s oceans in this manner—and to deny other countries the use of the world’s oceans for taking actions against U.S. interests—constitutes an immense asymmetric advantage for the United States. As discussed elsewhere (see “Defense Primer: Geography, Strategy, and U.S. Force Design), the size and composition of U.S. naval forces reflect the position of the United States as a Western Hemisphere power with a goal of preventing the emergence of regional hegemons in Eurasia. As a result, the U.S. Navy includes significant numbers of aircraft carriers, nuclear-powered attack submarines, large surface combatants, large amphibious ships, and underway replenishment ships. Navy Ship Types The Navy’s ballistic missile submarines (SSBNs) are dedicated to performing a singular mission of strategic nuclear deterrence. The Navy’s other ships, which are sometimes referred to as the Navy’s general-purpose ships, are generally multimission ships capable of performing a variety of missions other than strategic nuclear deterrence. The principal types of general-purpose ships in the Navy include attack submarines (SSNs); aircraft carriers (CVNs); large surface combatants, meaning cruisers (CGs) and destroyers (DDGs); small surface combatants, meaning frigates (FFGs), Littoral Combat Ships (LCSs), patrol craft (PCs), and mine warfare (MIW) ships; amphibious ships, whose primary function is to transport Marines and their equipment and supplies to distant operating areas and support Marine ship-to-shore movements and Marine operations ashore; combat logistics force (CLF) ships, which perform underway replenishment (UNREP) operations, meaning the at-sea resupply of combat ships; and other support ships of various types. wing aircraft, plus a few helicopters. Each CVW typically includes 40 or more strike fighters that are capable of air-toground (strike) and air-to-air (fighter) combat operations. Size of the Navy The total number of ships in the Navy is a one-dimensional metric that leaves out many other important factors bearing on naval capability. Notwithstanding this limitation, observers often cite the total number of ships in the U.S. Navy as a convenient way of summarizing the Navy’s capabilities. The quoted number of ships in the Navy reflects the battle force ships counting method, which is a set of rules for which ships count (or do not count) toward the quoted number of ships. The battle force ships counting method was established in the early 1980s and has been modified by legislation in recent years. Essentially, it includes ships that are readily deployable overseas, and which contribute to the Navy’s overseas combat capability. The Naval History and Heritage Command maintains a database on numbers of ships in the Navy from 1886 to the present. (It is available here: https://www.history.navy.mil/research/ histories/ship-histories/us-ship-force-levels.html.) Since this database extends back to 1886, it uses a different counting method that is more suitable for working with older historical data. This alternate counting method, however, produces, for the 1980s onwards, figures for the total size of the Navy that are different than the figures produced by the battle force ships counting method. For this reason, using figures from the NHHC database to quote the size of the Navy in recent years can cause confusion. Navy Force-Level Goal The Navy determines its force-level goal—the size and composition of the fleet it would like to reach and maintain in coming years—through a Force Structure Analysis (FSA). FSAs are conducted every few years. For each type of ship, the FSA calculates the number required for warfighting, and the number required for maintaining dayto-day forward-deployed presence overseas. Navy officials then work with these two calculations to select a final required number for each ship type. The Navy’s current force-level goal, released in December 2016, is to reach and maintain a fleet of 355 battle force ships, including 66 SSNs, 12 CVNs, 104 large surface combatants, 52 smaller surface combatants, and 38 amphibious ships. Section 1025 of the FY2018 National Defense Authorization Act (H.R. 2810/P.L. 115-91 of December 12, 2017) states “It shall be the policy of the United States to have available, as soon as practicable, not fewer than 355 battle force ships, comprised of the optimal mix of platforms, with funding subject to the availability of appropriations or other funds.” The Navy’s aircraft carriers embark multimission carrier air wings (CVWs) consisting of 60+ aircraft—mostly fixedhttps://crsreports.congress.gov Defense Primer: Naval Forces Actual Size of the Navy The size of the Navy in recent years has generally ranged between 270 and 290 battle force ships. As of September 18, 2019, the figure was 290. (The current total figure can be found here: http://www.navy.mil/navydata/ nav_legacy.asp?id=146.) In its FY2020 budget submission, the Navy had projected that at the end of FY2020, the Navy would include 301 ships. Nuclear-Powered Ships The Navy’s submarines and aircraft carriers are all nuclear powered, meaning that they use on-board nuclear reactors to generate power for propulsion and for running shipboard equipment. Navy submarines each have one reactor; Navy aircraft carriers each have two. All other Navy ships are conventionally powered, meaning that they burn petroleumbased fuels for propulsion and shipboard power. Navy Nuclear Weapons The Navy maintains a neither-confirm-nor-deny (NCND) policy regarding the presence or absence of nuclear weapons on specific ships. In general, however, it is understood that the only Navy ships that carry nuclear weapons are SSBNs, which carry nuclear-armed submarine-launched ballistic missiles (SLBMs). All of the Navy’s other nuclear weapons, which were referred to collectively as non-strategic naval nuclear weapons, were withdrawn from the fleet as part of a unilateral initiative announced by President George H.W. Bush at the end of the Cold War in 1991. Navy Formations Naval forces are modular and scalable—Navy ships can be combined into formations of various types and sizes that are tailored for their intended missions. The two most prominent types of naval formations are carrier strike groups (CSGs) and amphibious ready groups (ARGs). The composition of a CSG can vary, but typically includes a CVN with its embarked CVW, perhaps three to five surface combatants (typically one cruiser, plus some destroyers), a CLF ship, and perhaps an SSN. An ARG typically includes three amphibious ships—one LHA/LHD type “big deck” amphibious assault ship (which resembles a medium-sized aircraft carrier) and two smaller (but still sizeable) amphibious ships known as LPDs and LSDs. An ARG typically embarks a Marine Expeditionary Unit (MEU), which includes more than 2,000 Marines and their equipment (including some aircraft) and supplies. A third type of naval formation is a Surface Action Group (SAG), which consists of a few or several surface combatants, without an aircraft carrier. Navy ships sometimes operate by themselves—all SSBNs and many SSNs operate this way, as do some surface combatants and amphibious ships that are deployed to lower-threat areas (such as South America or parts of Africa) for purposes of engaging with allied or partner forces in those areas. Forward-Deployed Operations Western Pacific and the Indian Ocean/Persian Gulf region. At any given moment, 30% or more of the Navy, including two or three CSGs and two or three ARGs, might be forward-deployed. Having enough ships to maintain these forward deployments is a major influence on calculations that determine the Navy’s force-level goal. The forward-deployed presence of Navy ships is intended to support a number of ongoing or potential missions, including deterrence of potential aggressors; reassurance of allies and partners; engagement operations with foreign naval and other military forces (which can strengthen political bonds and improve interoperability between the Navy and those other forces); intelligence, surveillance, and reconnaissance (ISR) operations; rapid response in humanitarian assistance/disaster response (HA/DR) situations; non-combatant evacuation operations (NEOs); counter-terrorist operations, crisis response and containment, and timely initial actions during the early (and potentially critical) stages of a conflict. Forward-Homeported Ships Most of the Navy’s ships are homeported in the United States. To help support its ability to maintain its forwarddeployed presence, some Navy ships are homeported in forward locations. The Navy’s largest forward-homeporting location is Japan, where a CSG, an ARG, and some mine warfare ships are homeported. Additional Navy ships are forward-homeported elsewhere in the Pacific, in the Persian Gulf (at Bahrain), and in the Mediterranean (in Spain and Italy). Relevant Statutes Title 10, U.S. Code, Subtitle C – Navy and Marine Corps CRS Products CRS Report RL32665, Navy Force Structure and Shipbuilding Plans: Background and Issues for Congress, by Ronald O'Rourke Other Resources Congressional Budget Office, The U.S. Military’s Force Structure: A Primer, July 2016, particularly Chapter 3 (pp. 45-79) Department of the Navy, Highlights of the Department of the Navy FY2020 Budget, accessed July 26, 2019, at https://www.secnav.navy.mil/fmc/fmb/Documents/20pres/Budg et%20Highlights%20Book.pdf U.S. Navy Program Guide 2017, accessed December 4, 2017, at http://www.navy.mil/strategic/npg17.pdf Ronald O'Rourke, Specialist in Naval Affairs The U.S. Navy is unique among the world’s navies in that, at any given moment, a sizeable fraction of the Navy is forward-deployed to distant operating areas, particularly the https://crsreports.congress.gov IF10486 Defense Primer: Naval Forces Disclaimer This document was prepared by the Congressional Research Service (CRS). CRS serves as nonpartisan shared staff to congressional committees and Members of Congress. It operates solely at the behest of and under the direction of Congress. Information in a CRS Report should not be relied upon for purposes other than public understanding of information that has been provided by CRS to Members of Congress in connection with CRS’s institutional role. CRS Reports, as a work of the United States Government, are not subject to copyright protection in the United States. Any CRS Report may be reproduced and distributed in its entirety without permission from CRS. However, as a CRS Report may include copyrighted images or material from a third party, you may need to obtain the permission of the copyright holder if you wish to copy or otherwise use copyrighted material. https://crsreports.congress.gov | IF10486 · VERSION 11 · UPDATED