Updated November 8, 2018
Defense Primer: Naval Forces
“Naval Forces” Refers to Both the Navy
wing aircraft, plus a few helicopters. Each CVW typically
and Marine Corps
includes 40 or more strike fighters that are capable of air-to-
Although the term “naval forces” is often used to refer
ground (strike) and air-to-air (fighter) combat operations.
specifically to Navy forces, it more properly refers to both
Navy and Marine Corps forces, because both the Navy and
Size of the Navy
Marine Corps are naval services. For further discussion, see
The total number of ships in the Navy is a one-dimensional
“Defense Primer: Department of the Navy.” For a
metric that leaves out many other important factors bearing
discussion of the Marine Corps that focuses on its
on naval capability. Notwithstanding this limitation,
operations as a ground-combat force, see “Defense Primer:
observers often cite the total number of ships in the U.S.
Ground Forces.”
Navy as a convenient way of summarizing the Navy’s
capabilities.
U.S. Strategy and Naval Forces
U.S. naval forces give the United States the ability to
The quoted number of ships in the Navy reflects the battle
convert the world’s oceans—a global commons that covers
force ships counting method, which is a set of rules for
more than two-thirds of the planet’s surface—into a
which ships count (or do not count) toward the quoted
medium of maneuver and operations for projecting U.S.
number of ships. The battle force ships counting method
power ashore and otherwise defending U.S. interests around
was established in the early 1980s and has been modified
the world. The ability to use the world’s oceans in this
by legislation in recent years. Essentially, it includes ships
manner—and to deny other countries the use of the world’s
that are readily deployable overseas, and which contribute
oceans for taking actions against U.S. interests—constitutes
to the Navy’s overseas combat capability. The Naval
an immense asymmetric advantage for the United States.
History and Heritage Command maintains a database on
numbers of ships in the Navy from 1886 to the present. (It
As discussed elsewhere (see “Defense Primer: Geography,
is available here: https://www.history.navy.mil/research/
Strategy, and U.S. Force Design), the size and composition
histories/ship-histories/us-ship-force-levels.html.) Since this
of U.S. naval forces reflect the position of the United States
database extends back to 1886, it uses a different counting
as a Western Hemisphere power with a goal of preventing
method that is more suitable for working with older
the emergence of regional hegemons in Eurasia. As a result,
historical data. This alternate counting method, however,
the U.S. Navy includes significant numbers of aircraft
produces, for the 1980s onwards, figures for the total size of
carriers, nuclear-powered attack submarines, large surface
the Navy that are different than the figures produced by the
combatants, large amphibious ships, and underway
battle force ships counting method. For this reason, using
replenishment ships.
figures from the NHHC database to quote the size of the
Navy in recent years can cause confusion.
Navy Ship Types
The Navy’s ballistic missile submarines (SSBNs) are
Navy Force-Level Goal
dedicated to performing a singular mission of strategic
The Navy determines its force-level goal—the size and
nuclear deterrence. The Navy’s other ships, which are
composition of the fleet it would like to reach and maintain
sometimes referred to as the Navy’s general-purpose ships,
in coming years—through a Force Structure Analysis
are generally multimission ships capable of performing a
(FSA). FSAs are conducted every few years. For each type
variety of missions other than strategic nuclear deterrence.
of ship, the FSA calculates the number required for
The principal types of general-purpose ships in the Navy
warfighting, and the number required for maintaining day-
include attack submarines (SSNs); aircraft carriers
to-day forward-deployed presence overseas. Navy officials
(CVNs); large surface combatants, meaning cruisers
then work with these two calculations to select a final
(CGs) and destroyers (DDGs); small surface combatants,
required number for each ship type. The Navy’s current
meaning frigates (FFGs), Littoral Combat Ships (LCSs),
force-level goal, released in December 2016, is to reach and
patrol craft (PCs), and mine warfare (MIW) ships;
maintain a fleet of 355 battle force ships, including 66
amphibious ships, whose primary function is to transport
SSNs, 12 CVNs, 104 large surface combatants, 52 smaller
Marines and their equipment and supplies to distant
surface combatants, and 38 amphibious ships. Section 1025
operating areas and support Marine ship-to-shore
of the FY2018 National Defense Authorization Act (H.R.
movements and Marine operations ashore; combat logistics
2810/P.L. 115-91 of December 12, 2017) states: “It shall be
force (CLF) ships, which perform underway replenishment
the policy of the United States to have available, as soon as
(UNREP) operations, meaning the at-sea resupply of
practicable, not fewer than 355 battle force ships,
combat ships; and other support ships of various types.
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 fixed-
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Defense Primer: Naval Forces
Actual Size of the Navy
Western Pacific and the Indian Ocean/Persian Gulf region.
The size of the Navy in recent years has generally ranged
At any given moment, 30% or more of the Navy, including
between 270 and 290 battle force ships. As of November 8,
two or three CSGs and two or three ARGs, might be
2018, the figure was 286. (The current total figure can be
forward-deployed. Having enough ships to maintain these
found here: http://www.navy.mil/navydata/nav_legacy.asp?
forward deployments is a major influence on calculations
id=146”.) In its FY2019 budget submission, the Navy had
that determine the Navy’s force-level goal.
projected that at the end of FY2018, the Navy would
include 292 ships.
The forward-deployed presence of Navy ships is intended
to support a number of ongoing or potential missions,
Nuclear-Powered Ships
including deterrence of potential aggressors; reassurance of
The Navy’s submarines and aircraft carriers are all nuclear
allies and partners; engagement operations with foreign
powered, meaning that they use on-board nuclear reactors
naval and other military forces (which can strengthen
to generate power for propulsion and for running shipboard
political bonds and improve interoperability between the
equipment. Navy submarines each have one reactor; Navy
Navy and those other forces); intelligence, surveillance, and
aircraft carriers each have two. All other Navy ships are
reconnaissance (ISR) operations; rapid response in
conventionally powered, meaning that they burn petroleum-
humanitarian assistance/disaster response (HA/DR)
based fuels for propulsion and shipboard power.
situations; non-combatant evacuation operations (NEOs);
counter-terrorist operations, crisis response and
Navy Nuclear Weapons
containment, and timely initial actions during the early (and
The Navy maintains a neither-confirm-nor-deny (NCND)
potentially critical) stages of a conflict.
policy regarding the presence or absence of nuclear
weapons on specific ships. In general, however, it is
Forward-Homeported Ships
understood that the only Navy ships that carry nuclear
Most of the Navy’s ships are homeported in the United
weapons are SSBNs, which carry nuclear-armed
States. To help support its ability to maintain its forward-
submarine-launched ballistic missiles (SLBMs). All of the
deployed presence, some Navy ships are homeported in
Navy’s other nuclear weapons, which were referred to
forward locations. The Navy’s largest forward-homeporting
collectively as non-strategic naval nuclear weapons, were
location is Japan, where a CSG, an ARG, and some mine
withdrawn from the fleet as part of a unilateral initiative
warfare ships are homeported. Additional Navy ships are
announced by President George H.W. Bush at the end of
forward-homeported elsewhere in the Pacific, in the Persian
the Cold War in 1991.
Gulf (at Bahrain), and in the Mediterranean (in Spain and
Italy).
Navy Formations
Naval forces are modular and scalable—Navy ships can be

combined into formations of various types and sizes that are
Relevant Statutes
tailored for their intended missions. The two most
prominent types of naval formations are carrier strike
Title 10, U.S. Code, Subtitle C – Navy and Marine Corps
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
CRS Products
destroyers), a CLF ship, and perhaps an SSN. An ARG
CRS Report RL32665, Navy Force Structure and Shipbuilding
typically includes three amphibious ships—one LHA/LHD
Plans: Background and Issues for Congress, by Ronald O'Rourke
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
Other Resources
equipment (including some aircraft) and supplies. A third
Congressional Budget Office, The U.S. Military’s Force Structure:
type of naval formation is a Surface Action Group (SAG),
A Primer, July 2016, particularly Chapter 3 (pp. 45-79)
which consists of a few or several surface combatants,
Department of the Navy, Highlights of the Department of the
without an aircraft carrier.
Navy FY2019 Budget, accessed October 23, 2018, at
http://www.secnav.navy.mil/fmc/fmb/Documents/19pres/Highli
Navy ships sometimes operate by themselves—all SSBNs
ghts_book.pdf
and many SSNs operate this way, as do some surface
combatants and amphibious ships that are deployed to
U.S. Navy Program Guide 2017, accessed December 4, 2017, at
lower-threat areas (such as South America or parts of
http://www.navy.mil/strategic/npg17.pdf
Africa) for purposes of engaging with allied or partner
forces in those areas.

Forward-Deployed Operations
Ronald O'Rourke, Specialist in Naval Affairs
The U.S. Navy is unique among the world’s navies in that,
IF10486
at any given moment, a sizeable fraction of the Navy is
forward-deployed to distant operating areas, particularly the
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Defense Primer: Naval Forces


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