U.S. Periods of War and Dates of
Recent Conflicts
Updated June 5, 2020
Congressional Research Service
https://crsreports.congress.gov
RS21405

U.S. Periods of War and Dates of Recent Conflicts

Summary
Many wars or conflicts in U.S. history have federal y designated “periods of war,” dates marking
their beginning and ending. These dates are important for qualification for certain veterans’
pension or disability benefits. Confusion can occur because beginning and ending dates for
“periods of war” in many nonofficial sources are often different from those given in treaties and
other official sources of information, and armistice dates can be confused with termination dates.
This report lists the beginning and ending dates for “periods of war” found in Title 38 of the Code
of Federal Regulations, dealing with the Department of Veterans Affairs (VA). It also lists and
differentiates other beginning dates given in declarations of war, as wel as termination of
hostilities dates and armistice and ending dates given in proclamations, laws, or treaties. The
dates for the recent conflicts in Afghanistan and Iraq are included along with the official end date
for Operation New Dawn in Iraq on December 15, 2011, and Operation Enduring Freedom in
Afghanistan on December 28, 2014. Operation Inherent Resolve continues along the Syrian-Iraqi
border effective October 15, 2014.
For additional information, see the following CRS Products: CRS In Focus IF10539, Defense
Primer: Legal Authorities for the Use of Military Forces, by Jennifer K. Elsea; CRS Report
R42699, The War Powers Resolution: Concepts and Practice, by Matthew C. Weed; CRS Report
RL31133, Declarations of War and Authorizations for the Use of Military Force: Historical
Background and Legal Implications, by Jennifer K. Elsea and Matthew C. Weed.
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U.S. Periods of War and Dates of Recent Conflicts

War Dates
Congress, usual y through a declaration of war, has often been the first governmental authority to
designate the beginning date of a war or armed conflict. The President, or executive branch
officials responsible to him, through proclamation, or Congress, through legislation, has been
responsible for designating the war’s termination date.1 In some cases, later legislation is enacted
to extend these beginning and ending dates for the purpose of broadening eligibility for veterans’
benefits.2 This report notes the variations in the dates cited in the Code of Federal Regulations
(C.F.R.) “periods of war” and those dates given in the declarations of war beginning and the
proclamations, laws, or treaties terminating such conflicts.3 Adding to the confusion, during
World War II, wars were declared and terminated with six individual combatant countries.
Moreover, armistice dates are also often confused with termination dates.4
Title 38, Part 3, Section 3.2 of the Code of Federal Regulations, dealing with the Department of
Veterans Affairs (VA), lists official beginning and termination dates for most war periods from the
Indian Wars to the present to be used in determining the availability of veterans’ benefits.5 The
material below summarizes these dates. Where applicable, a summary of the Department of
Veterans Affairs official beginning and termination dates is provided followed by a citation to the
lettered C.F.R. section. For some entries, this initial summary is followed by an explanatory note
or declaration, armistice, cease-fire, or termination dates cited by other official sources. Also
included are dates for the recent conflicts in Iraq and Afghanistan.
Indian Wars
January 1, 1817, through December 31, 1898, inclusive. Service must have been rendered with
U.S. military forces against Indian tribes or nations. Code of Federal Regulations, 3.2 (a).
Spanish-American War
April 21, 1898, through July 4, 1902, inclusive. If the veteran served with the U.S. military forces
engaged in hostilities in the Moro Province, the ending date is July 15, 1903. The Philippine

1 For background on the War Powers Act and use of military force abroad, see the following: CRS Report RL31133,
Declarations of War and Authorizations for the Use of Military Force: Historical Background and Legal Im plications ,
by Jennifer K. Elsea and Matthew C. Weed; CRS In Focus IF10539, Defense Prim er: Legal Authorities for the Use of
Military Forces, by Jennifer K. Elsea; and CRS Report R42699, The War Powers Resolution: Concepts and Practice,
by Matthew C. Weed.
2 T he American Legion also follows these dates closely in determining who is eligible for membership; the Veterans of
Foreign Wars has its own much more elaborate list of dates.
3 Code of Federal Regulation (C.F.R.) T itle 38, Part 3, §3.2 Periods of war, at https://ecfr.io/T itle-38/
pt38.1.3#se38.1.3_12.
4 Armistice—“In International law, a suspension or temporary cessation of hostilities by agreement between belligerent
powers.” Department of Defense Dictionary of Military and Associated Terms, Joint Publication 1-02, Department of
Defense, 12 April 2010, on p. 36 at https://fas.org/irp/doddir/dod/jp1_02-april2010.pdf.
5 T itle 38 of the C.F.R., titled “Pensions, Bonuses and Veterans’ Relief,” is not to be confused with T itle 38 of the
United States Code, titled “ Veterans Benefits.” Laws enacted in each Congress are first collected as session laws,
published in the Statutes at Large for each session. T hese laws are then codified by subject and published in the United
States Code. T he general guidance given by these laws results in the issuance of more detailed regula tions to
implement these laws. Such regulations are first published in the Federal Register and are then codified by subject in
the C.F.R.
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Insurrection and the Boxer Rebel ion are included for the purposes of benefit determination under
this C.F.R. section. Code of Federal Regulations, 3.2 (b).
Declared by an act of Congress April 25, 1898 (30 Stat. 364, Ch. 189). An armistice signed
August 12, 1898. Terminated by Treaty signed at Paris, December 10, 1898 (30 Stat. 1754),
ratified and proclaimed April 11, 1899.
Mexican Border Period
May 9, 1916, through April 5, 1917. In the case of a veteran who during such period served in
Mexico, on the borders thereof, or in the adjacent waters thereto. Code of Federal Regulations,
3.2 (h).
World War I
April 6, 1917, through November 11, 1918, inclusive. If the veteran served with the U.S. military
forces in Russia, the ending date is April 1, 1920. Service after November 11, 1918, and before
July 2, 1921, is considered World War I service if the veteran served in the active military, naval,
or air service after April 5, 1917, and before November 12, 1918. Code of Federal Regulations,
3.2 (c).
World War I Against Germany
Declared by Joint Resolution of Congress of April 6, 1917 (40 Stat. 429, Ch. 1). Armistice signed
near Compiègne, France, November 11, 1918. Terminated July 2, 1921, by Joint Resolution of
Congress (42 Stat. 105, Ch. 40, 1).
World War I Against Austria-Hungary
Declared by Joint Resolution of Congress, December 7, 1917 (40 Stat. 429, Ch. 1). An armistice
signed near Compiègne, France, November 11, 1918. Terminated July 2, 1921, by Joint
Resolution of Congress (42 Stat. 106, Ch. 40, 3).
World War II
December 7, 1941, through December 31, 1946, inclusive. If the veteran was in service on
December 31, 1946, continuous service before July 26, 1947, is considered World War II service.
Code of Federal Regulations, 3.2 (d).
During World War II, war was official y declared against six separate countries. The war with
each was not over until the effective date of the Treaty of Peace. Note also the confusion cited
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below over which day is the official Victory in Europe Day (V-E Day)6 and Victory over Japan
Day (V-J Day).7
World War II with Germany
Declared by Joint Resolution of Congress, December 11, 1941 (55 Stat. 796, Ch. 564). German
representative Colonel General Alfred Jodl signed the unconditional act of surrender to Al ied
representatives in a schoolhouse in Reims, France, on May 7, 1945. A second German surrender
ceremony was held on May 8 in Berlin at the insistence of the U.S.S.R. Cessation of hostilities
declared as of noon, December 31, 1946, by presidential proclamation of December 31, 1946
(Proc. no. 2714, 61 Stat. 1048). State of war with the “government of Germany” terminated
October 19, 1951, by Joint Resolution of Congress of that date (65 Stat. 451, Ch. 519), by
Presidential Proclamation 2950, October 24, 1951. No peace treaty with Germany was signed.
World War II with Japan
Declared by Joint Resolution of Congress, December 8, 1941 (55 Stat. 795, Ch. 561). Japanese
representatives publicly signed unconditional surrender document on the deck of the USS
Missouri anchored in Tokyo Bay on September 2, 1945. President Truman proclaimed this date
Victory over Japan Day or V-J Day. Cessation of hostilities declared as of 12 noon, December 31,
1946, by presidential proclamation of December 31, 1946 (Proc. no. 2714, 61 Stat. 1048).
Terminated by Multilateral Treaty of Peace with Japan, signed at San Francisco, September 8,
1951 (3 UST 3329), and ratified March 20, 1952, effective April 28, 1952.
World War II with Italy
Declared by Joint Resolution of Congress, December 11, 1941 (55 Stat. 797, Ch. 565). Cessation
of hostilities declared as of noon December 31, 1946, by presidential proclamation of December

6 May 7, 1945, is listed as V-E Day in commentary about signing the first German surrender document in Historic
Docum ents of World War II by Walter Consuelo Langsam (Westport, CT : Greenwood Press, 1958), p. 144. However,
May 8, 1945, is cited as V-E day in The Encyclopedia of Am erican Facts and Dates, p. 528; as the “ Official V-E Day”
in Louis L. Snyder, Louis L. Snyder’s Historical Guide to World War Two (Westport, CT : Greenwood, 1982), p. 736;
and the World Alm anac of World War II, ed. Brigadier Peter Young (New York: Pharos Books, 1981), p. 347, states in
its chronology for May 8, “T he British and Americans celebrate VE Day (Victory in Europe Day). T ruman, Churchill
and King George VI all make special broadcasts.” Although President T ruman did not officially proclaim May 7 as V-
E (Victory in Europe) Day, he did proclaim Sunday, May 13, 1945, a day of prayer. T o make for more confusion, his
May 8, 1945, Proclamation 2651, proclaiming May 13 as a day of prayer, is titled, “Victory in Europe; Day of Prayer”
(3 C.F.R., 1943-1948 Comp.), p. 55. In addition, his May 8 news conference in which he proclaims May 13 a day of
prayer is titled, “ T he President’s News Conference on V-E Day”—Public Papers of the Presidents of the United States.
Harry S. Trum an, 1945 (Washington: GPO, 1961), p. 43.
7 In his news conference of August 14, 1945, announcing news of the Japanese government’s complete acceptance of
terms of surrender, President T ruman states, “Proclamation of V-J Day must wait upon the formal signing of the
surrender terms by Japan.”—Public Papers, p. 216. T he proclamation of September 2 as V-J Day was given in his
September 1, 1945, “ Speech to the American People after the Signing of the T erms of Unconditional Surrender by
Japan.”—Public Papers, p. 254. However, no formal, numbered proclamation was apparently issued. Both August 14,
the day of President T ruman’s announcement of the Japanese surrender, and September 2, the official day proclaimed
by President T ruman in his speech, are cited as V-J Day in Chase’s Calendar of Events 2002 (New York: McGraw-
Hill, 2002), pp. 421 and 555. August 15 is cited as V-J Day by The Encyclopedia of Am erican Facts and Dates, 9th ed.,
by Gordon Carruth (New York: Harper Collins, 1993), p. 530. August 15, on which the Japanese Emperor made his
historic broadcast to the Japanese people telling of Japan’s surrender, is cited as V-J Day in The World Almanac of
World War II, p. 353.
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31, 1946 (Proc. no. 2714, 61 Stat. 1048). Terminated by Treaty of Peace dated at Paris, February
10, 1947 (61 Stat. 1247), effective September 15, 1947.
World War II with Bulgaria
Declared by Joint Resolution of Congress, June 5, 1942 (56 Stat. 307, Ch. 323). Cessation of
hostilities declared as of noon December 31, 1946, by presidential proclamation of December 31,
1946 (Proc. no. 2714, 61 Stat. 1048). Terminated by Treaty of Peace dated at Paris, February 10,
1947 (61 Stat. 1915), effective September 15, 1947.
World War II with Hungary
Declared by Joint Resolution of Congress, June 5, 1942 (56 Stat. 307, Ch. 324). Cessation of
hostilities declared as of noon December 31, 1946, by presidential proclamation (Proc. no. 2714,
61 Stat. 1048). Terminated by Treaty of Peace dated at Paris, February 10, 1947 (61 Stat. 1757),
effective September 15, 1947.
World War II with Romania
Declared by Joint Resolution of Congress, June 5, 1942 (56 Stat. 307, Ch. 325). Cessation of
hostilities declared as of noon December 31, 1946, by presidential proclamation of December 31,
1946 (Proc. no. 2714, 61 Stat. 1048). Terminated by Treaty of Peace dated at Paris, February 10,
1947 (61 Stat. 1757), effective September 15, 1947.
Korean Conflict
June 27, 1950, through January 31, 1955, inclusive. Code of Federal Regulations, 3.2 (e).
On June 25, 1950, North Korean Communist forces attacked South Korean positions south of the
38th paral el, leading to an immediate United Nations (U.N.) Security Council resolution cal ing
for a cease-fire and withdrawal of the North Korean forces. On June 26, President Truman
ordered U.S. air and sea forces in the Far East to aid South Korea. On June 27, the U.N. Security
Council adopted a resolution asking U.N. members for assistance in repel ing the North Korean
armed attack and in restoring peace and security in the area. On June 30, the President stated that
he had authorized the use of certain U.S. air and ground units wherever necessary. No declaration
of war was requested of Congress and no authorization for use of force, by statute, was requested
or enacted. An armistice signed at Panmunjom, Korea, on July 27, 1953, between U.N. and
Communist representatives (4 UST 234; TIAS 2782). No peace treaty was ever signed.
Vietnam Era
The period beginning on February 28, 1961, and ending on May 7, 1975, inclusive, in the case of
a veteran who served in the Republic of Vietnam during that period. The period beginning on
August 5, 1964, and ending on May 7, 1975, inclusive, in al other cases. Code of Federal
Regulations, 3.2 (f).
Tonkin Gulf Resolution
No declaration of war was requested of Congress. Instead, there was a Joint Resolution of
Congress to promote the maintenance of international peace and security in Southeast Asia, which
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stated in part that Congress “approves and supports the determination of the President, as
Commander in Chief, to take al necessary measures to repel any armed attack against the forces
of the United States and to prevent any further aggression.” H.J. Res. 1145, P.L. 88-408, August
10, 1964 (78 Stat. 384). The Tonkin Gulf Resolution was formal y repealed on January 12, 1971,
by P.L. 91-672, (84 Stat. 2055). The Agreement Ending the War and Restoring Peace in Vietnam
signed in Paris, January 27, 1973 (TIAS 7674). Joint communiqué implementing the agreement
and protocols of January 27, 1973, signed at Paris and entered into force, June 13, 1973.
Conflicts in Lebanon 1982-1983, Grenada 1983, and
Panama 1989-1990
Lebanon. U.S. Marines deployed on August 21, 1982 and September 29, 1982, were part of a
temporary multinational force in Lebanon. See S. 639, P.L. 98-43 (Lebanon Emergency
Assistance Act of 1983).8
Grenada. On October 25, 1983, U.S. troops were deployed to Grenada “to restore law and order”
and to protect American lives at the request of the members of the Organization of Eastern
Caribbean States. Known as Operation Urgent Fury,9 by December 15, 1983, al forces had been
withdrawn.
Panama. On December 21, 1989, President George H.W. Bush reported that he had ordered U.S.
military forces to Panama to protect the lives of American citizens and bring General Noriega to
justice. Known as Operation Just Cause,10 by February 13, 1990, al the invasion forces had been
withdrawn.
Note: Participation in these conflicts alone does not confer automatic veterans’ status for
servicemembers. For more information, see CRS Report R42324, Who Is a “Veteran”?—Basic
Eligibility for Veterans’ Benefits, by Scott D. Szymendera, and CRS Report RL31133,
Declarations of War and Authorizations for the Use of Military Force: Historical Background
and Legal Implications, by Jennifer K. Elsea and Matthew C. Weed.
Persian Gulf War
August 2, 1990, through April 6, 1991, when Iraq official y accepted cease-fire terms. Congress
passed H.J.Res. 77, Authorizing the Use of Military Force Against Iraq, the same day it was
introduced (January 12, 1991), and it was signed by President George H.W. Bush on January 14,
1991 (P.L. 102-1). Operation Desert Storm11 and the air war phase began at 3 a.m. January 17,
1991 (January 16, 7 p.m. Eastern Standard Time). Al ied ground assault began at 4 a.m. February

8 “See also S.J.Res. 159 (P.L. 98-119) authorizing the President to keep U.S. forces in Lebanon for as long as 18
months, or until April 1985; and “A Reluctant Congress Adopts Lebanon Policy,” CQ Almanac 1983 at
https://library.cqpress.com/cqalmanac/document.php?id=cqal83 -1198422.
9 Ronald H. Cole, Operation Urgent Fury The Planning and Execution of Joint Operations in Grenada 12 October - 2
Novem ber 1983, Joint History Office, Office of the Chairman of the Joint Chiefs of Staff, Washington, DC 1997, at
https://www.jcs.mil/Portals/36/Documents/History/Monographs/Urgent_Fury.pdf .
10 Ronald H. Cole, Operation Just Cause The Planning and Execution of Joint Operations in Panama February 1988 –
January 1990, Joint History Office, Office of the Chairman of the Joint Chiefs of Staff, Washington, DC 1995, at
https://www.jcs.mil/Portals/36/Documents/History/Monographs/Just_Cause.pdf .
11 Shannon Collins, “Desert Storm: A Look Back,” DOD News Feature, January 11 2019, at
https://www.defense.gov/Explore/Features/story/Article/1728715/desert -storm-a-look-back/.
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24 (February 23, 8 p.m. EST). Cease-fire declared at 8:01 a.m. February 28, 1991 (12:01 a.m.
EST).12 Cease-fire terms negotiated at Safwan, Iraq, March 1, 1991.13 Iraq official y accepted
cease-fire terms, April 6, 1991.14 Cease-fire took effect April 11, 1991. Currently, the Code of
Federal Regulations, 3.2 (i) does not list an official end date.15
Recent Conflicts: Afghanistan and Iraq
Shortly after the terrorist attacks in the United States on September 11, 2001, President George W.
Bush cal ed on Afghanistan’s leaders to hand over Osama bin Laden and other al Qaeda leaders
and close their terrorist training camps. He also demanded the return of al detained foreign
nationals and the opening of terrorist training sites to inspection.16 These demands were rejected.
The Administration sought international support from the United Nations (U.N.) for military
action against Afghanistan. U.N. Security Council Resolution 1368 of September 12, 2001, stated
that the Council “Expresses its readiness to take al necessary steps to respond to the terrorist
attacks of September 11, 2001 ... ”17 This resolution was interpreted by many as U.N.
authorization for military action in response to the 9/11 attacks. As a result, Congress passed
S.J.Res. 23, “Authorization for Use of Military Force,” on September 14, 2001. This bil was
signed by President George W. Bush on September 18, 2001, as P.L. 107-40, and it authorized the
President to use “al necessary and appropriate force against those nations, organizations, or
persons he determines planned, authorized, committed, or aided the terrorist attacks that occurred
on September 11, 2001, or harbored such organizations or persons. . ”18 Operations in the region
began with U.S. military forces deployed to the region on October 7, 2001.
Afghanistan—Operation Enduring Freedom (OEF)
Operations began with U.S. military forces deployed to Afghanistan to combat terrorism on
October 7, 2001, and designated Operation Enduring Freedom.
On March 27, 2009, President Barack Obama announced a new strategy in Afghanistan and
Pakistan and ordered the deployment of 17,000 troops that had been previously requested by
General David McKiernan.19 In President Obama’s “Address to the Nation on the Way Forward

12 Cease fire—“A command given to any unit or individual firing any weapon to stop engaging the target.” Department
of Defense Dictionary, p. 67.
13 T his agreement is actually a transcript of the discussion held at Safwan Airfield, Iraq, between Coalition participants,
U.S. Gen. M. Norman Schwarzkopf and Lt. Gen. Khalid of the Joint Arab Forces, and Iraqi participants, Lt. Gen.
Sultan Kasim Ahmad, Chief of Staff of the Ministry of Defense, and Lt. Gen. Sala Abud Mahmud, III Corps
Commander.
14 Acceptance is in the form of a letter to the U.N. Security Council accepting the terms of U.N. Resolution 687 (U.N.
document S22485, April 11, 1991).
15 38 C.F.R. Part 3, §3.2 Periods of war, at http://www.ecfr.gov/cgi-bin/text-idx?rgn=div5&node=
38:1.0.1.1.4#se38.1.3_12. Note: Section (i) for the Persian Gulf War lists “ August 2, 1990, through date to be
prescribed by Presidential proclamation or law.” No specific end date is listed as of the date of this report.
16 President George W. Bush, “Address Before A Joint Session of Congress on the United States Response to the
T errorist Attacks of September 11,” September 20, 2001, p. 57/PDF p. 65, at https://georgewbush-
whitehouse.archives.gov/infocus/bushrecord/documents/Selected_Speeches_George_W_Bush.pdf.
17 United Nations, Security Council Resolution 1368 (2001), adopted by the Security Council at its 4370th meeting, on
September 12, 2001, at https://www.treasury.gov/resource-center/sanctions/Documents/1368.pdf.
18 P.L. 107-40, “To authorize the use of United States Armed Forces against those responsible for the recent attacks
launched against the United States,” at http://www.gpo.gov/fdsys/pkg/PLAW-107publ40/pdf/PLAW-107publ40.pdf.
19 T he White House, Office of the Press Secretary, “Remarks by the President on a New Strategy for Afghanistan and
Pakistan,” press release, March 27, 2009, at https://obamawhitehouse.archives.gov/the-press-office/remarks-president -
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in Afghanistan and Pakistan” at West Point on December 1, 2009, he stated that “it is in our vital
national interest to send an additional 30,000 U.S. troops to Afghanistan. After 18 months, our
troops wil begin to come home. These are the resources that we need to seize the initiative, while
building the Afghan capacity that can al ow for a responsible transition of our forces out of
Afghanistan.”20
On June 22, 2011, President Obama again addressed the American people about the way forward
in Afghanistan: “We wil begin the drawdown of U.S. troops from a position of strength. We have
exceeded our expectations on our core goal of defeating al-Qaeda kil ing 20 of its top 30 leaders,
including Osama bin Laden. We have broken the Taliban’s momentum, and trained over 100,000
Afghan National Security Forces.”21 As a result, U.S. forces began the withdrawal of 10,000
troops from Afghanistan.
On December 28, 2014, after 13 years of combat operations, President Obama and Secretary of
Defense Chuck Hagel announced the end of OEF, a conflict that claimed the lives of more than
2,200 American troops, and the beginning of a follow-on mission on January 1, 2015.22 A
transition ceremony was held at the International Security and Assistance Force headquarters in
Kabul, Afghanistan, attended by U.S. commanders and al ied troops from the North Atlantic
Treaty Organization (NATO). For more information, see CRS Report RL30588, Afghanistan:
Post-Taliban Governance, Security, and U.S. Policy, by Kenneth Katzman and Clayton Thomas.
Afghanistan—Operation Freedom’s Sentinel (OFS)
Effective January 1, 2015, Secretary of Defense Hagel announced that the U.S. mission in
Afghanistan would focus on training, advising, and assisting Afghan security forces and
designated it as Operation Freedom’s Sentinel.23 During 2015, approximately 13,000 troops, with
nearly 10,000 from the United States, were deployed alongside NATO’s 28 member nations and
13 partner nations for its Resolute Support Mission (RSM).24 RSM focused on training, advising,
and assisting (TAA) the Afghan Security Institutions (ASI) and the Afghan National Defense &
Security Forces (ANDSF) in order to build their capabilities and long-term sustainability.25 On

a-new-strategy-afghanistan-and-pakistan.
20 T he White House, Office of the Press Secretary, “Remarks by the President in Address to the Nation on the Way
Forward in Afghanistan and Pakistan,” press release, December 1, 2009, at https://obamawhitehouse.archives.gov/the-
press-office/remarks-president -address-nation-way-forward-afghanistan-and-pakistan.
21 T he White House, Office of the Press Secretary, “Remarks by the President on the Way Forward in Afghanistan,”
press release, June 22, 2011, at https://obamawhitehouse.archives.gov/the-press-office/2011/06/22/remarks-president -
way-forward-afghanistan.
22 U.S. Department of Defense (DOD), “Obama, Hagel Mark End of Operation Enduring Freedom,” news release,
December 28, 2014, at https://dod.defense.gov/News/Article/Article/603860/obama-hagel-mark-end-of-operation-
enduring-freedom/.
23 DOD, “Statement by Secretary of Defense Chuck Hagel on Operation Enduring Freedom and Operation Fr eedom’s
Sentinel,” news release, NR-631-14, December 28, 2014, at https://dod.defense.gov/News/News-Releases/News-
Release-View/Article/605332/statement -by-secretary-of-defense-chuck-hagel-on-operation-enduring-freedom-and/.
24 NAT O Resolute Support Mission (RSM) “placemat”: Key Facts and Figures, at
https://www.nato.int/nato_static_fl2014/assets/pdf/pdf_2019_06/20190625_2019-06-RSM-Placemat.pdf. As of June
2019, there were 17,148 troops from 39 nations including the Unit ed States. Note on numbers: T he number of troops
above reflects the overall contribution of individual contributing nations. T hey should be taken as indicative as they
change daily, in accordance with the deployment procedures of the individual troop -contributing nations.
25 NAT O, Resolute Support Mission in Afghanistan, March 2, 2020, at
https://www.nato.int/cps/en/natohq/topics_113694.htm . At the 2016 NATO Summit in Warsaw, Allied leaders decided
to extend the presence of RSM beyond 2016. T wo years later, at the Brussels Summit in July 2018, they committed to
sustaining the mission until conditions indicate a change is appropriate. On February 29, 2020, NAT O welcomed the
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October 1, 2015, General John F. Campbel , commander, RSM, U.S. Forces-Afghanistan/ISAF,
defined the U.S. military’s objectives: “U.S. forces are now carrying out two wel -defined
missions: a Counter-Terrorism (CT) mission against the remnants of Al-Qaeda and the Resolute
Support TAA mission in support of Afghan security forces. Our CT and TAA efforts are
concurrent and complementary. While we continue to attack the remnants of Al-Qaeda, we are
also building the ANDSF so that they can secure the Afghan people, win the peace, and contribute
to stability throughout the region.”26 On October 15, 2015, President Obama announced that the
posture of 9,800 U.S. troops in Afghanistan would remain through 2016. By the end of 2016,
5,500 troops were expected to remain in Afghanistan to support the U.S. embassy in Kabul and at
bases in Bagram, Jalalabad, and Kandahar to train Afghans and focus on counterterrorism
operations in the region.27
On August 21, 2017, President Donald Trump announced his strategy in Afghanistan and South
Asia in a speech at Fort Myer, VA. He stated, “In Afghanistan and Pakistan, America’s interests
are clear: We must stop the resurgence of safe havens that enable terrorists to threaten America,
and we must prevent nuclear weapons and materials from coming into the hands of terrorists and
being used against us, or anywhere in the world for that matter.”28
On September 2, 2018, Army General John M. Nicholson passed command of NATO’s Resolute
Support Mission and U.S. Forces Afghanistan to Army General Austin S. Mil er during a
ceremony in Kabul, Afghanistan.29 General Mil er emphasized to coalition troops that what they
are doing in Afghanistan makes their own countries and citizens safer. The “train, advise, assist”
mission al ows Afghan security forces to take the fight to the enemy, and to give the Afghan
government the security needed to provide stability and no longer a safe haven for terrorists.30
See CRS Report R44853, Additional Troops for Afghanistan? Considerations for Congress, by
Kathleen J. McInnis and Andrew Feickert, for more background information.
Iraq—Operation Iraqi Freedom (OIF)
In mid-2002, the George W. Bush Administration began deploying U.S. troops to Kuwait. During
the 107th Congress (2001-2002), Congress debated whether to send U.S. troops to Iraq, and on
October 16, 2002, H.J.Res. 114 was signed into law as P.L. 107-243, Authorization for the Use of

announcement that “ significant first steps in pursuit of a peaceful settlement, paving the way for intra -Afghan
negotiations between a fully inclusive Afghan national team and the T aliban to reach a comprehensive peace
agreement.” See also CRS Report R45122, Afghanistan: Background and U.S. Policy: In Brief, by Clayton T homas in
the section “ U.S.-T aliban Agreement.”
26 Gen. John F. Campbell, commander, Resolute Support Mission, U.S. Forces-Afghanistan/ISAF, “Operation
Freedom’s Sentinel and our continued security investment in Afghanistan,” Army.mil, October 1, 2015, at
https://www.army.mil/article/156517/
operation_freedoms_sentinel_and_our_continued_security_investment_in_afghanistan.
27 T he White House, Office of the Press Secretary, “Statement by the President on Afghanistan,” October 15, 2015, at
https://obamawhitehouse.archives.gov/the-press-office/2015/10/15/statement-president -afghanistan.
28 T he White House, Briefings and Statements, “Remarks by President T rump on the Strategy in Afghanistan and South
Asia,” August 21, 2017, at https://www.whitehouse.gov/briefings-statements/remarks-president-trump-strategy-
afghanistan-south-asia/.
29 Jim Garamone, “Miller T akes over NAT O, U.S. Commands in Afghanistan,” DOD News, September 2, 2018, at
https://dod.defense.gov/News/Article/Article/1618550/miller-takes-over-nato-us-commands-in-afghanistan/.
30 Jim Garamone, “Commander Wants Coalition Forces in Afghanist an to Know Why T hey Fight,” DOD News,
September 29, 2018, at https://dod.defense.gov/News/Article/Article/1649125/commander-wants-coalition-forces-in-
afghanistan-to-know-why-they-fight/.
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Military Force Against Iraq Resolution of 2002. This law authorized the President to use military
force to “defend the national security of the United States against the continuing threat posed by
Iraq” and “to enforce al relevant U.N. Security Council resolutions against Iraq.”31
On November 8, 2002, the U.N. Security Council adopted Resolution 1441. This resolution found
Iraq in breach of past U.N. resolutions prohibiting stockpiling and importing weapons of mass
destruction (WMDs).32 The Hussein government in Iraq continued to be uncooperative with U.N.
investigators, which heightened the situation through spring 2003.
In an address to the nation on March 17, 2003, President George W. Bush gave Iraqi President
Saddam Hussein and his sons a 48-hour ultimatum to leave Iraq.33 On March 19, 2003, President
Bush announced to the nation that the early stages of military operations against Iraq had begun
and designated them Operation Iraqi Freedom (OIF).34
On May 1, 2003, in an address to the nation, President Bush declared that “major military combat
actions in Iraq have ended,”35 yet U.S. troops remained in Iraq.
A ceremony at Camp Victory in Baghdad on January 1, 2010, marked the end of the
Multinational Forces-Iraq (MNF-I) and the beginning of United States Forces-Iraq (USF-I),
which merged five major command groups into one single headquarters command.36 As General
David Petraeus, head of U.S. Central Command (CENTCOM), noted, “This ceremony marks
another significant transition here in Iraq. It represents another important milestone in the
continued drawdown of American Forces.”37 Troops from 30 countries have served in MNF-I
since 2003.
On August 31, 2010, President Obama announced that the American combat mission in Iraq had
ended. A transitional force of U.S. troops remained in Iraq with a different mission: advising and
assisting Iraq’s security forces, supporting Iraqi troops in targeted counterterrorism missions, and
protecting U.S. civilians.38
On May 20, 2020, President Donald J. Trump issued a Notice to Congress: “... in accordance with
section 202(d) of the National Emergencies Act (50 U.S.C. 1622(d)), I am continuing for 1 year
the national emergency with respect to the stabilization of Iraq declared in Executive Order
13303.”39

31 P.L. 107-243, “Authorization for the use of Military Force against Iraq Resolution of 2002,” at
https://www.congress.gov/107/plaws/publ243/PLAW-107publ243.pdf.
32 United Nations, Security Council Resolution 1441 adopted on November 8, 2002, at its 4644th meeting at
http://www.un.org/Depts/unmovic/documents/1441.pdf.
33 U.S. President (G.W. Bush), “Address to the Nation on Iraq,” Weekly Compilation of Presidential Documents, March
24, 2003, vol. 39, no. 12, pp. 338-341.
34 Ibid, pp. 342-343.
35 Ibid, May 5, 2003, vol. 39, no. 18, pp. 516-518.
36 Staff Sgt. Luke Koladish and Sgt. Kat Briere, “ New Command Marks Milestone in Iraq,” U.S. Army website,
January 2, 2010, at http://www.army.mil/article/32437/New_command_marks_milestone_in_Iraq/.
37 Ibid.
38 T he White House, Office of the Press Secretary, “Remarks by the President in Address to the Nation on the End of
Combat Operations in Iraq,” August 31, 2010, at https://obamawhitehouse.archives.gov/the-press-office/2010/08/31/
remarks-president -address-nation-end-combat-operations-iraq.
39 T he White House, Office of the Press Secretary, “Notice Regarding the Continuation of the National Emergency
With Respect to the Stabilization of Iraq,” May 20, 2020, at https://www.whitehouse.gov/briefings-statements/text-
notice-continuation-national-emergency-respect-stabilization-iraq-2/; and E.O. 13303, May 22, 2003, at
https://www.govinfo.gov/content/pkg/WCPD-2003-05-26/pdf/WCPD-2003-05-26-Pg646.pdf.
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Iraq—Operation New Dawn (OND)
Effective September 1, 2010, the military operations in Iraq acquired a new official designation:
Operation New Dawn.40 A short ceremony marked the transfer in which Army General Ray
Odierno passed command of USF-I to Army General Lloyd J. Austin. On December 15, 2011,
U.S. Armed Forces in Baghdad marked the official end of the war in Iraq. The Chairman of the
Joint Chiefs of Staff and other top U.S. military leaders observed the official end of U.S. Forces
Iraq’s mission after nearly nine years of conflict that claimed the lives of nearly 4,500 U.S.
troops.41 On the military side of Baghdad International Airport, Army General Martin E.
Dempsey, Defense Secretary Leon E. Panetta, Army General Lloyd J. Austin III, commanding
general of U.S. Forces Iraq, and U.S. Ambassador to Iraq James F. Jeffrey addressed U.S. and
Iraqi officials and more than 150 troops and media from around the world.42 For more
information, see CRS Report R45025, Iraq: Background and U.S. Policy, by Christopher M.
Blanchard, and CRS In Focus IF10404, Iraq and U.S. Policy, by Christopher M. Blanchard.
Islamic State-Operation Inherent Resolve (OIR)
Effective October 15, 2014, the DOD designated U.S. and coalition operations “Operation
Inherent Resolve”43 against the terrorist group the Islamic State in Iraq and the Levant (ISIL,
another name for the Islamic State) along the Syrian-Iraqi border. The commander of U.S. 3rd
Army and Army Forces Central Command was designated the commander of the Combined Joint
Task Force–Operation Inherent Resolve (CJTF-OIR) on October 17, 2014.44 Airstrikes by U.S.
and coalition forces continue.45 As of June 30, 2017, the total cost of operations related to ISIS
since kinetic operations started on August 8, 2014, was $14.3 bil ion and the average daily cost is
$13.6 mil ion for 1,058 days of operations.46 For more information, see CRS Report R44135,
Coalition Contributions to Countering the Islamic State, by Kathleen J. McInnis, CRS In Focus
IF10328, The Islamic State, by Christopher M. Blanchard and Carla E. Humud.

Author Information

Barbara Salazar Torreon

Senior Research Librarian

40 U.S. Army, “Operation New Dawn,” August 31, 2010, at https://www.army.mil/article/44526/operation_new_dawn.
41 Cheryl Pellerin, “Dempsey: Iraq Campaign Was worth the Cost,” DOD News, December 15, 2011, at
http://archive.defense.gov/news/newsarticle.aspx?id=66488.
42 Ibid.
43 DOD, Operation Inherent Resolve, at http://www.inherentresolve.mil/About-Us/.
44 CJT F-OIR, Combined Joint T ask Force Operation Inherent Resolv e at https://dod.defense.gov/OIR/, and Fact Sheet
at http://www.inherentresolve.mil/Portals/14/Documents/Mission/History.pdf?ver=2016-03-23-065243-743.
45 DOD, OIR Strike Releases 2015-present at https://www.inherentresolve.mil/Media-Library/Strike-Releases/.
46 DOD, OIR, “Cost of Operations” at https://dod.defense.gov/OIR/Cost/. Note: Weekly Islamic State of Iraq and the
Levant (ISIL) Cost Report through June 30, 2017, the latest reported.
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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 n ot 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
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Congressional Research Service
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