Defense Primer: President’s Constitutional Authority with Regard to the Armed Forces
Updated December 14, 2022
Defense Primer: President’s Constitutional Authority with
Regard to the Armed Forces
Article II, Section 2, Clause 1
this inquiry.” During the War of 1812, the Court recognized
The President shall be Commander in Chief of the Army
in Brown v. United States that Congress was empowered by
and Navy of the United States, and of the Militia of the
the Constitution to authorize the confiscation of enemy
several States, when called into the actual Service of the
property during wartime, but that, absent such
United States....
authorization, a seizure authorized by the President was
void.
Commander in Chief—Early Supreme
Court Cases
In the Prize Cases, the Supreme Court sustained the
The Constitution expressly makes the President
blockade of southern ports instituted by President Lincoln
Commander in Chief of the Armed Forces, but does not
in April 1861, at a time when Congress was not in session.
define exactly what powers he may exercise in that role.
Congress ratified the President’s actions at the first
Nor does it explain the extent to which Congress, using its
opportunity available, so it was not necessary for the Court
own constitutional powers, may influence how the President
to consider the constitutional basis of the President’s action
commands the Armed Forces. Separation-of-powers
in the absence of congressional authorization or in the face
debates arise with some frequency over the exercise of
of any prohibition. Nevertheless, the Court approved the
military powers.
blockade five-to-four as an exercise of presidential power
alone, holding that a state of war was a fact and that,
Early in the nation’s history, Alexander Hamilton wrote in
because the nation was under attack, the President was
The Federalist, No. 69, that the Commander in Chief power
bound to act without waiting for Congress. This case has
is “nothing more than the supreme command and direction
frequently been cited to support claims of greater
of the military and naval forces, as first general and admiral
presidential autonomy by reason of the President’s role as
of the confederacy.” Concurring in that view in 1850, the
Commander in Chief.
Supreme Court in Fleming v. Page stated that “[the
President’s] duty and his power are purely military. As
The Supreme Court has also suggested that the President
Commander-in-Chief, he is authorized to direct the
has some independent authority to employ the Armed
movements of the naval and military forces placed by law
Forces, at least in the absence of contrary congressional
at his command, and to employ them in the manner he may
action. In the 1890 case of In re Neagle, the Supreme Court
deem most effectual to harass and conquer and subdue the
suggested, in dictum, that the President has the power to
enemy.”
deploy the military abroad to protect or rescue persons with
significant ties to the United States. Discussing examples of
In Little v. Barreme, Chief Justice Marshall had occasion to
the executive lawfully acting in the absence of express
recognize congressional war power and to deny the
statutory authority, Justice Miller approvingly described the
exclusivity of presidential power. After Congress had
Martin Koszta affair, in which an American naval ship
authorized limited hostilities with France, a U.S. vessel
intervened to prevent a lawful immigrant from being
under orders from the President seized what its commander
captured by an Austrian vessel, despite the absence of clear
believed was a U.S. merchant ship bound from a French
statutory authorization.
port, allegedly carrying contraband material. Congress had,
however, provided by statute only for seizure of such
20th Century Expansion of Presidential
vessels bound to French ports. The Court held that the
Commander-in-Chief Power
President’s orders exceeded the authority granted by
The expansion of presidential power related to war, asserted
Congress and were not to be given the force of law, even in
as a combination of Commander in Chief authority and the
the context of the President’s military powers and even
President’s inherent authority over the nation’s foreign
though the instructions might have been valid in the
affairs, began in earnest in the 20th century. In United States
absence of contradictory legislation.
v. Curtiss-Wright Export Corp., the Supreme Court
confirmed that the President enjoys greater discretion when
In Bas v. Tingy, the Court looked to congressional
acting with respect to matters of foreign affairs than may be
enactments rather than plenary presidential power to uphold
the case when only domestic issues are involved. In that
military conduct related to the limited war with France. In
case, Congress, concerned with the outside arming of the
Talbot v. Seeman, the Court upheld as authorized by
belligerents in the war between Paraguay and Bolivia, had
Congress a U.S. commander’s capture of a neutral ship,
authorized the President to proclaim an arms embargo if he
holding that “[t]he whole powers of war being, by the
found that such action might contribute to a peaceful
constitution of the United States, vested in congress, the
resolution of the dispute. President Franklin Roosevelt
acts of that body can alone be resorted to as our guides in
issued the requisite finding and proclamation, and Curtiss-
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Defense Primer: President’s Constitutional Authority with Regard to the Armed Forces
Wright and associate companies were indicted for violating
anticipated hostilities would not rise to the level of a war in
the embargo. They challenged the statute, arguing that
the constitutional sense.”
Congress had failed adequately to elaborate standards to
guide the President’s exercise of the power thus delegated.
In January 2020, President Trump ordered a strike against
Writing for the Court, Justice Sutherland concluded that the
an Iranian target in Iraq, killing Qasem Soleimani, the head
limitations on delegation in the domestic field were
of the Islamic Revolutionary Guard Corps-Quds Force
irrelevant where foreign affairs are involved. This outcome
(IRGC-QF), and Abu Mahdi al Muhandis, an Iraqi security
was based on the premise that foreign relations is
official and founder of Kata’ib Hizballah, an organization
exclusively an executive function combined with the
deemed responsible for attacks against U.S. and U.S.
constitutional model positing that internationally, the power
partner forces in Iraq. The Trump Administration
of the federal government is not one of enumerated but of
subsequently submitted a report to Congress describing a
inherent powers.
change to existing legal and policy frameworks governing
the use of armed force. In the report, the Trump
Presidential Uses of Force
Administration explained that
Presidents from Truman to Biden have claimed independent
authority to commit U.S. Armed Forces to involvements
Article II of the United States Constitution,
abroad absent any congressional participation, other than
empowers the President, as Commander in Chief, to
consultation and after-the-fact financing. In 1994, for
direct the use of military force to protect the Nation
example, President Clinton asserted authority to order the
from an attack or threat of imminent attack and to
participation of U.S. forces in NATO actions in Bosnia-
protect important national interests. Article II thus
Herzegovina based on what his Administration viewed as
authorized the President to use force against forces
the President’s “constitutional authority to conduct U.S.
of Iran, a state responsible for conducting and
foreign relations” and role as Commander in Chief.
directing attacks against United States forces in the
Additionally, President Clinton protested congressional
region.
efforts to restrict the use of military forces there and
elsewhere as an improper and possibly unconstitutional
The report also cited the 2002 authorization for the use of
limitation on his “command and control” of U.S. forces.
military force against Iraq in support of the operation.
In March 2011, President Obama ordered U.S. military
President Biden in 2021 ordered airstrikes against Iran-
forces to take action as part of an international coalition to
backed militia targets in Iraq and Syria in response to rocket
enforce U.N. Security Council Resolution 1973. Resolution
attacks against U.S. targets in Iraq, citing his “constitutional
1973 authorized U.N. Member States to take all necessary
authority to conduct United States foreign relations and as
measures (other than through military occupation) to
Commander in Chief and Chief Executive” rather than any
protect civilians from attacks by the Libyan government
congressional authorizations for use of military force. The
and to establish a no-fly zone over the country. Although
Biden Administration reported to Congress that it is
these operations had not been authorized by legislation, the
conducting an interagency review of its use of military
executive branch submitted a report to Congress that
force policy and conduct of related national security
claimed the President has the “constitutional authority, as
operations under “extant authorizations and delegations of
Commander in Chief and Chief Executive and pursuant to
presidential authority with respect to these matters.”
his foreign affairs powers, to direct such limited military
operations abroad.”
CRS Products
In 2018, President Trump ordered airstrikes against three
CRS Report R42699, The War Powers Resolution: Concepts and
chemical weapons facilities in Syria, where U.S. troops
Practice, by Matthew C. Weed.
were engaged in armed conflict against the Islamic State
CRS Report R42738, Instances of Use of United States Armed
(ISIS). The U.S. Armed Forces also have at times engaged
Forces Abroad, 1798-2022, by Barbara Salazar Torreon and
Syrian government targets on the justification of defending
Sofia Plagakis
partner forces under the extant authorizations for the use of
CRS Report RL31693, U.S. Armed Forces Abroad: Selected
military force against terrorist groups responsible for the
Congressional Votes Since 1982, by Barbara Salazar Torreon and
attacks of September 11, 2001, and against Iraq in 2002.
Carla Y. Davis-Castro.
These authorizations arguably do not go so far as to permit
extension of the conflict to the Syrian government. After
the first airstrikes, the Office of Legal Counsel advised the
Trump Administration that attacks on Syrian government
targets are within the President’
Jennifer K. Elsea, Legislative Attorney
s Commander-in-Chief
powers without need for congressional approval because
IF10534
the President “had reasonably determined that the use of
force would be in the national interest and that the
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Defense Primer: President’s Constitutional Authority with Regard to the Armed Forces
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https://crsreports.congress.gov | IF10534 · VERSION 10 · UPDATED