INSIGHTi
Iraq: Attacks and U.S. Strikes Reopen
Discussion of U.S. Military Presence
Updated January 29, 2024
Iran-backed armed groups have attacked U.S. personnel in Iraq more than fifty times since the October 7,
2023, Hamas-led attacks on Israel and the onset of the war in Gaza. In response President Joe Biden has
ordered U.S. air strikes in Iraq and in neighboring Syria. Iraq’s government, citing risks to Iraq’s security
from the attacks and counter-strikes, says it will seek to end the presence in Iraq of the U.S.-led Global
Coalition to Defeat the Islamic State (IS, aka ISIS/ISIL) and to engage in bilateral discussions about the
future of the U.S. military presence. On January 25, Secretary of Defense Lloyd Austin announced plans
to start U.S.-Iraq talks on the “evolution” of the coalition mission and to “enable the transition to an
enduring bilateral security partnership.”
In December 2023, President Biden cited the Iraqi government’s invitation for U.S. forces and the
coalition to remain in Iraq in his semi-annual comprehensive war powers report to Congress. That same
month, U.S. Central Command reported that approximately 2,400 U.S. military personnel were deployed
in Iraq and 800 in Syria. The U.S. military presence in Iraq and U.S. military access to Iraq’s airspace and
land border with Syria facilitate U.S. military operations in Syria, where IS insurgents are more active and
U.S. partner forces secure prisons holding thousands of IS fighters.
In December 2023, Congress authorized U.S. counter-IS partnership programs in Iraq and Syria through
December 2024. Members of Congress may consider how potential changes to the U.S. and/or coalition
presence in Iraq may affect U.S. interests in the region; whether changes should be made to patterns of
U.S. assistance to Iraqi and Syrian partners; whether additional consultation with the executive branch or
oversight is warranted; and how attacks on U.S. personnel and U.S. strikes comport with the War Powers
Resolution and the 2001 and 2002 legislative authorizations for the use of military force.
Escalating Attacks and U.S. Strikes Follow Hamas-led Attacks on Israel
and Onset of Gaza War
Following the U.S. killing in Iraq of Iran’s Islamic Revolutionary Guards Corps (IRGC)-Qods Force
commander Qassem Soleimani and an Iraqi security official (both U.S.-designated terrorists) in January
2020, Iraq’s parliament voted to direct the Iraqi government to expel foreign forces and deny foreign
access to Iraqi airspace, territory, and waters. Iraq’s then-caretaker government did not do so, and its
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successors engaged U.S. counterparts in talks that led in December 2021 to an announced end to U.S.
combat operations and a transition to training and advisory support. Intermittent attacks on U.S. forces in
Syria and Iraq continued through early 2023, with some attributed to Iran-backed Iraqi armed groups.
Observers noted changes in the pattern of such attacks in relation to developments in Iraq, Syria, and the
wider region. President Biden directed strikes following some attacks on U.S. personnel in Syria and Iraq,
and the Administration has stated its intent to defend U.S. personnel with “proportional” responses.
Since October 2023, observers have documented more than 150 claimed attacks by the “Islamic
Resistance in Iraq” on U.S. and other targets in Iraq, Syria, Israel, and Jordan, including the January 28
attack in Jordan that killed and injured U.S. servicemembers. Some attacks in Syria and Iraq have resulted
in injuries to U.S. and Iraqi personnel. Reportedly, U.S. response strikes have destroyed facilities of the
IRGC and of an Iran-backed Iraqi group in Syria and Iraq and have killed some members of the Iraqi
groups inside Iraq. Iraq’s government has described attacks on U.S. forces as acts hostile to Iraq while
saying U.S. strikes on its territory violate Iraqi sovereignty. A January 4, 2024 U.S. strike in Baghdad
killed a leader of an Iran-backed U.S.-designated terrorist group who also served as a commander in
Iraq’s state-affiliated Popular Mobilization Forces.
Figure 1. Attacks on U.S. Personnel and U.S. Strikes in Iraq and Syria
Since October 17, 2023, and as of January 24, 2024
Source: CRS, using U.S. Department of Defense announcements and media reports. On October 24, 2023, the
Department of Defense acknowledged 13 attacks on U.S. forces since October 17, 2023.
Notes: KH – Kata’ib Hezbol ah. HN – Harakat al Nujaba. CRS cannot validate reported attack and strike details.
Possible Considerations for Congress
Secretary of Defense Lloyd Austin has said U.S. forces remain “focused on the mission of defeating
Daesh [IS/ISIS/ISIL], and we are here for no other purpose” and in January 2024 he reiterated U.S.
“commitment to deepen our security cooperation to advance stability within Iraq and the region.” In
August 2023, a U.S.-Iraq Joint Security Cooperation Dialogue agreed “to consult on a future process ...
inclusive of the Coalition, to determine how the Coalition’s military mission will evolve on a timeline
according to the following factors: the threat from ISIS, operational and environmental requirements, and
[Iraqi] capability levels.” As part of those discussions, the Iraqi government “reaffirmed its commitment
to protect U.S. and Global Coalition personnel and advisors, convoys, and diplomatic facilities.”
A U.S.-Iraq Higher Military Commission (HMC) is set to begin meetings that could result in substantial,
partial, or no changes to the U.S. military presence. A Pentagon spokesperson has said “The HMC
meeting is not a negotiation about the withdrawal of U.S. forces from Iraq.” In considering possible
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outcomes, executive branch requests for regular and supplemental funding, and defense authorization
provisions in 2024, Congress may consider the following questions:
• How essential is the U.S. and coalition military presence in Iraq? How does the U.S.
military presence in Iraq relate to U.S. efforts to counter and deter Iran? How does it
affect risks of wider conflict?
• How might changes to the U.S. and/or coalition presence in Iraq affect:
• U.S. operations in Syria? U.S. embassy security? the NATO mission in Iraq?
• Iraq’s security and regional security?
• relationships between Iraqi groups and the Iraqi government, including the Kurdistan
Regional Government and U.S.-supported peshmerga forces?
• How might abrupt changes affect perceptions of the United States?
• How if at all should U.S. defense and foreign assistance funding and authorities evolve?
Author Information
Christopher M. Blanchard
Specialist in Middle Eastern Affairs
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.
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