Updated December 20, 2018
Defense Primer: Commanding U.S. Military Operations
Military operations, both in peacetime and in war, are an
The Chain of Command
inherently complex undertaking. One key to success,
Title 10 U.S.C. §162 specifies that the chain of command
therefore, is a clear, unified chain of command. This
for military operations goes from the President, to the
enables senior leaders in the U.S. government—in
Secretary of Defense, to Commanders of Combatant
particular, the President and the Secretary of Defense—to
Commands. The Chairman of the Joint Chiefs of Staff acts
command and control military forces around the world.
as an intermediary, transmitting orders between the
Secretary of Defense and the Commanders of Combatant
A (Very) Brief History of the Chain of Command
Commands. Each Combatant Commander is a four-star
The way that the United States commands and controls its
Flag or General Officer, whose appointment is confirmed
forces is in large part a product of an inherent tension
by the Senate.
between improving the effectiveness of U.S. forces, on the
one hand, and preserving civilian control of the military, on
Unified Command Plan (UCP)
the other. The experience of World War II convinced
The UCP is a classified executive branch document that
President Truman, among others, that a greater degree of
articulates how DOD assigns responsibility for different
coordination and integration between the U.S. military
missions and areas of the world. It is prepared by the
services was necessary to improve the conduct of military
Chairman of the Joint Chiefs of Staff every two years and
operations. Yet there was concern at the time that
approved by the President. Each UCP sets forth basic
integrating these institutions might result in an overly
guidance to all unified combatant commanders; establishes
powerful military staff element that could threaten the
their missions, responsibilities, and force structure;
principle of civilian control of U.S. forces.
delineates the general geographical area of responsibility
for geographic combatant commanders; and specifies
The resulting compromise was to create a Joint Chiefs of
functional responsibilities for functional combatant
Staff, comprising all the military service chiefs, and headed
commanders. Congress is not included in this review
by a Chairman, serving as an advisory body only. As a
process but does have visibility into issues affecting UCP
corporate body, it was specifically not designed to exercise
development. It is through the UCP that the Department of
command; the Chairman of the Joint Chiefs of Staff (CJCS)
Defense develops its global map of areas of responsibilities
had no command authority. The Joint Chiefs of Staff did,
for its Combatant Commanders, reflected below.
however, have responsibility for establishing “unified
combatant commands,” which were charged with executing
Figure 1. Combatant Commanders’ Area of
military operations in different parts of the world and
Responsibility
combining the capabilities of two or more military services.
Different service chiefs were assigned executive and
administrative responsibilities for these combatant
commands, which gave them a de facto mechanism through
which they could influence ongoing military operations.
By 1953, the authority to establish Combatant Commands
(COCOMs) was assigned to the Secretary of Defense,
although the relative ambiguity of the chain of command
remained a feature of DOD operations until 1986.
Perceived shortcomings in the U.S. chain of command led
to demonstrable failures during several incidents in the late
1970s and early 1980s. The military services, in the view of
many observers, failed to effectively plan or conduct
operations jointly due to confusion over whether the
military services or unified combatant commanders were
Source: U.S. Department of Defense.
ultimately in charge of operations. These incidents include
the operation in Grenada; the Iranian hostage rescue attempt
The Combatant Commands Today
(often referred to as “Desert One”); and the bombing of the
A COCOM is a military command with broad continuing
Marine Barracks in Beirut, Lebanon. In 1986, Congress
missions under a single commander and composed of
passed the Goldwater-Nichols Defense Reform Act (P.L.
significant assigned components of two or more military
99-433), which mandated clarifications to the chain of
departments. There are currently nine Combatant
command. The current command and control architecture
Commands. The COCOMs, and by extension their
for DOD is a product of these congressionally mandated
commanders, have responsibility for the military’s
changes.
operations in their respective area of responsibility during
both peacetime and war.
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Defense Primer: Commanding U.S. Military Operations
There are six regionally focused COCOMS, which operate
Of note, DOD has stated its intention to establish a United
in clearly delineated areas of operation and have a
States Space Command as part of a broader effort to
distinctive regional military focus:
rationalize U.S. military space activities.
U.S. Africa Command (USAFRICOM), responsible for
Service Component Commands
sub-Saharan Africa. It is located at Kelley Barracks,
Service Component Commands consist of organizations,
Stuttgart, Germany.
individuals, units, detachments, and/or support forces that
belong to a particular military service but are assigned to a
U.S. European Command (USEUCOM), responsible for
Combatant Commander. As an example, U.S. Army Europe
all of Europe, large portions of Central Asia, parts of the
(USAREUR) and U.S. Naval Forces, Europe
Middle East, and the Arctic and Atlantic Oceans. It is
(USNAVEUR) are both service component commands to
located at Patch Barracks, Stuttgart, Germany.
U.S. European Command (USEUCOM). These components
are subordinate to the Combatant Commander of the
U.S. Central Command (USCENTCOM), responsible
geographic theater in which they operate.
for most of the Middle East, parts of Northern Africa
and west Asia, and part of the Indian Ocean. It is located
The Laws Governing COCOMs
at MacDill Air Force Base, FL.
COCOMs are governed by the provisions contained in
Sections 161 through 168 of Title10, Armed Forces, U.S.
U.S. Northern Command (USNORTHCOM),
Code. These sections address the following provisions:
responsible for the defense of the continental United
States and coordination of security and military
Section 161: The establishment of COCOMs;
relationships with Canada and Mexico. It is located at
Peterson Air Force Base, CO.
Section 162: Chain of command and assignment of
forces for COCOMs;
U.S. Southern Command (USSOUTHCOM),
responsible for Central America, South America, and
Section 163: Role of the CJCS;
the Caribbean. It is located in Miami, FL.
Section 164: Assignment and powers and duties of
U.S. Indo-Pacific Command (USINDOPACOM),
commanders of COCOMs;
responsible for the Pacific Ocean, Southwest Asia,
Australia, south Asia, and part of the Indian Ocean. It
Section 165: Administration and support of COCOMs;
shares responsibility for Alaska with U.S. Northern
Command. It is located at Camp H.M. Smith, HI.
Section 166: COCOM budget proposals;
There are also four “functional” COCOMs, which operate
Section 166a: Funding COCOMs through the CJCS;
worldwide across geographic boundaries and provide
unique capabilities to geographic combatant commands and
Section 166b: Funding for combating terrorism
the services:
readiness initiatives;
U.S. Strategic Command (USSTRATCOM), responsible Section 167: Unified COCOMs for special operations
for controlling space, deterring attacks on the United
forces;
States and its allies, launching and operating satellite
systems, and directing the use of U.S. strategic forces.
Section 167a: Unified COCOMs for joint warfighting
It is located at Offutt Air Force Base, NE.
experimentation: acquisition authority; and
U.S. Special Operations Command (USSOCOM), which Section 168: Military-to-military and comparable
provides special forces, counter-paramilitary, counter-
activities.
narcotics, guerilla, psychological warfare, civil
education, and insurgency capabilities. It is located at
CRS Products
MacDill Air Force Base, FL.
CRS Report R44474, Goldwater-Nichols at 30: Defense Reform
U.S. Transportation Command (USTRANSCOM),
and Issues for Congress, by Kathleen J. McInnis
which provides air, land and sea transportation to
different components of DOD. It is located at Scott Air
Force Base, IL.
Kathleen J. McInnis, Analyst in International Security
U.S. Cyber Command (USCYBERCOM) directs,
synchronizes, and coordinates cyberspace planning and
IF10542
operations to defend and advance national interests in
collaboration with domestic and international partners.
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Defense Primer: Commanding U.S. Military Operations
Disclaimer
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