With his decision to end his bid for a second term, President Biden may now be considering how to cement his presidential legacy. One meaningful and historic step he could and should take is to formally end the Iraq War through a presidential proclamation. Such action would finally nullify the power of the outdated 2002 war authorization for that conflict and safeguard against its future abuse—including as the basis for a war with Iran.
Congressional Impasse
Executive action to address the authorization for the Iraq War is needed because Congress is at an impasse despite recent progress. In March 2023, the Senate voted by 66 to 30 for a joint resolution introduced by Senators Tim Kaine (D-VA) and Todd Young (R-IN) to repeal the 1991 Authorization for the Use of Military Force Against Iraq Resolution, P.L. 102-1 (1991 AUMF) and the Authorization for Use of Military Force Against Iraq Resolution of 2002, P.L. 107-243, (2002 Iraq AUMF)—respectively the authorizations for the 1991 Gulf and 2003 Iraq Wars. The Biden administration backed this move because these outdated war authorizations were no longer needed for U.S. military operations and the resolutions had obviously outlived their original purposes, given their original target—Saddam Hussein—no longer existed.
Yet notwithstanding strong bipartisan support for repeal in both chambers, the efforts to rescind these authorizations have stalled in the House of Representative as some House leaders have obstructed a floor vote. That this modest reassertion of congressional authority in matters of war and peace has been stymied is testament to the difficulties of any reform efforts on these matters.
The current blockage in the House—particularly given its potential use for a war with Iran— should prompt the White House to consider alternative means to disarm the 2002 Iraq AUMF. One reported reason that repeal legislation has yet to receive an up-or-down vote in the House is that some members are concerned about losing a potential authority for war with Iran. (The House of Representatives already voted to repeal the 2002 authorization in a previous Congress.) To be clear, it does not do so (see here and here). Nevertheless, a desire to keep the 2002 Iraq AUMF on the books as authority to fight Iran was certainly expressed by a number of senators who opposed repeal.
The courts have endorsed a solution to this dilemma. To prevent future abuse of this outdated authorization, President Biden should proclaim the conflict authorized by the 2002 resolution to be over and determine that it is no longer “necessary and appropriate” to use force for the purposes specified in the law.
The Executive Branch’s Reinterpretation of the 2002 Iraq AUMF
The 2002 Iraq AUMF was passed at the behest of President George W. Bush the year after the 9/11 attacks to address the supposed threat posed by Iraq’s alleged weapons of mass destruction as well as, inter alia, its purported connections with international terrorist organizations, including al Qaida.
The Resolution provides that the:
President is authorized to use the Armed Forces of the United States as he determines to be necessary and appropriate in order to—
(1) defend the national security of the United States against the continuing threat posed by Iraq; and
(2) enforce all relevant United Nations Security Council resolutions regarding Iraq.
The 2002 Iraq AUMF provided the domestic legal authority for the 2003 invasion and occupation of Iraq. However, the past three U.S. administrations have also invoked this resolution as the supposed legal basis to fight enemies other than the Iraqi Government helmed by Saddam Hussein. As recounted by Scott Anderson (here and here), successive U.S. presidents have relied upon the 2002 Iraq AUMF, often (and recently almost always) in conjunction with other legal authorities, to fight Shia armed groups such as the Mahdi Army and Iranian-backed militias as well as al-Qaeda in Iraq.
Following the 2011 withdrawal of U.S. forces from Iraq and their return in 2014 to combat the Islamic State, the Obama administration invoked the 2002 Iraq AUMF for a new purpose. It cited the 2002 resolution as a source of subsidiary authority, alongside the 2001 AUMF (which authorized the war on terror after the September 11, 2001 al Qaida attacks) for the military campaign against ISIS in Iraq and Syria. The Obama administration’s repurposing of these war authorizations was necessitated by the looming deadline imposed by the War Powers Resolution. The War Power Resolution requires the withdrawal of U.S. armed forces from hostilities after 60 days if not authorized by Congress. By claiming these laws represented prior congressional authorization, the Obama administration was able to circumvent the 60-day time limit and continue fighting ISIS without having to return to Congress for fresh authority. In relying upon the 2002 war authorization, the Obama administration seemed to reinterpret the 2002 Iraq AUMF’s objective of addressing the “threat posed by Iraq” to addressing the “threat posed from Iraq.”[1]
The Trump administration also invoked this 2002 resolution as a statutory basis for the killing of Iranian General Soleimani in 2020. In the case of the Soleimani strike, the Trump administration relied in part (the legal justification for the operation remains heavily redacted) on a theory that the 2002 law provided continuing authority to “establish a stable, democratic Iraq and address[] terrorist threats emanating from Iraq.” As Solemani was alleged undermining Iraqi stability, he fell within the scope of that use of force authorization.
Although the use of the 2002 Iraq AUMF to attack Iran has been critiqued by former senior U.S. national security lawyers and rejected by bipartisan majorities in both houses of Congress, the Trump administration nonetheless established a dangerous precedent. Indeed, the Trump administration’s legal justification for the Soleimani strike based on this 2002 resolution remains on the books in the form of legal opinion by the Department of Justice’s Office of Legal Counsel (OLC).
For most of its term, the Biden administration did not publicly invoke the 2002 Iraq AUMF as authority for military operations. From 2021 through 2023, the administration cited Article II of the Constitution as the sole authority for periodic U.S. airstrikes against so-called “Iran-backed militia groups” – paramilitaries in Iraq and Syria blamed for attacking U.S. forces in those countries. Despite the serious threat of escalation and the dangers to U.S. personnel located in the region, Article II was also cited when tit-for-tat attacks on and by U.S. troops resumed in October 2023 due to the Israel-Hamas war in Gaza.
But as frequent U.S. airstrikes against these Iran-backed groups persisted and the 60-day deadline imposed by the War Powers Resolution approached in late 2023, the Biden administration shifted legal rationales. The administration reported to Congress that both the 2002 and 2001 war authorizations provide authority for these hostilities. Thus, the White House could continue with strikes even in the absence of fresh authorization from Congress (as discussed in this recent report by the International Crisis Group, where I work).
So, like the Obama administration, the Biden White House is now invoking the 2002 AUMF as a source of subsidiary authority for military operations in Iraq and Syria. Also like the Obama administration, the Biden administration’s position reportedly nevertheless remains that the 2002 Iraq AUMF is not required for ongoing operations and that it still favors repealing the authorization.
Addressing this outdated Iraq war authorization is thus more than a matter of mere legislative hygiene. The 2002 Iraq AUMF remains susceptible to future abuse, specifically as purported authority to attack Iran and Iranian-backed groups. Republican Senators opposed to repealing the authorization explicitly emphasized the need to retain the Iraq AUMF not in order to achieve objectives specified in the resolution itself, but in order to fight Iran without going to Congress for authorization.
Presidential Proclamations and War Termination
To forestall such misuse of this outdated law, presidential action is necessary at least until Congress is able to rescind the resolution. Although rarely used, a unilateral presidential proclamation is a tool endorsed by the courts that the White House should seriously consider deploying here.
As expertly analyzed by David Simon (a former special counsel in the Pentagon’s Office of the General Counsel), over the course of U.S. history several different legal mechanisms for war termination have been used by the political branches. From the founding to the First World War, the most common means of legally ending a conflict was a peace treaty. This was true of both declared wars and undeclared wars such as the Quasi-War with France.
The exception was the Civil War—a domestic rebellion rather than a war between two sovereign countries—for which the Supreme Court relied on presidential proclamations to gauge the end of the conflict. In assessing when this “war of rebellion” ended for the purposes of applying a statute of limitations, the Supreme Court in The Protector looked to executive action. The Court observed that
“[a]cts of hostility by the insurgents occurred at periods so various, and of such different degrees of importance, and in parts of the country so remote from each other, both at the commencement and the close of the late civil war, that it would be difficult, if not impossible, to say on what precise day it began or terminated.”
Therefore, it was necessary to rely on “some public act of the political departments of the government” to fix the end date of the war. The Court thus turned to proclamations (here and here) issued by President Johnson in 1866 declaring the rebellion over in two sets of former Confederate states.
As Simon describes, treaty-based war termination began to break down with the First World War. The war with the Central Powers was terminated through a combination of treaties, congressional joint resolutions, and a presidential proclamation issued by President Harding—due in part to the Senate’s earlier refusal to provide advice and consent to ratification of the Treaty of Versailles under President Wilson. In the wake of the Senate’s negative vote on that treaty, the Supreme Court addressed the meaning of “conclusion of the present war” for the purposes of the Prohibition Act in Hamilton v. Kentucky Distilleries & Warehouse Co. The Court noted a “technical state of war” was “terminable only with the ratification of a treaty of peace or a proclamation of peace.”
Lower courts would subsequently cite Hamilton for the proposition that in “the absence of specific provision to the contrary the period of war extends to the ratification of the treaty of peace or the proclamation of peace.” The Supreme Court similarly looked to Hamilton in Ludecke v. Watkins, when in 1948 it evaluated whether a “declared war” (the Second World War) continued for the purposes of the Alien Enemy Act. But in Ludecke, the Court added that “the state of war may be terminated by treaty or legislation or Presidential proclamation.” (emphasis added).
In Application of Yamashita, the Supreme Court in 1946 also indicated that a proclamation would terminate a state of war and with it wartime authorities—including authority to prosecute enemy combatants for law of war violations. Yamashita, a Japanese general facing war crimes charges before a U.S. military commission, petitioned for a writ of habeas corpus challenging the lawfulness of his detention and trial including on the basis that the war between Japan and the United States was over. In rejecting this argument, the Court stated that “[w]e cannot say that there is no authority to convene a commission after hostilities have ended to try violations of the law of war committed before their cessation, at least until peace has been officially recognized by treaty or proclamation of the political branch of the Government.” (Emphasis added). As the Court observed, in 1946 despite the end of hostilities, “peace has not been agreed upon or proclaimed.” (Emphasis added.)
Congress has not declared war since the Second World War. With respect to the Korean War, into which President Truman committed U.S. armed forces without prior congressional authorization, U.S. military courts nonetheless found that a “state of war” existed for certain purposes under the Uniform Code of Military Justice even in the absence of a declaration of war. In 1954, the U.S. Army Board of Review concluded in U.S. v. Smith that such a state of war continued beyond the 1953 Korean armistice because “inasmuch as there has been no treaty, legislation, or Presidential proclamation ending the war in Korea, that war was still in existence on 4 April 1954.” (emphasis added).[2]
To the extent Congress has voted beforehand to authorize post-WWII conflicts, it has enacted authorizations for the use of military force (AUMFs) that are in many respects the functional equivalents of declarations of war. Although two such authorizations—the 1955 Formosa Resolution and the 1964 Gulf of Tonkin Resolution—contained provisions specifying the measures would expire upon certain determinations by the President, many have not.
Instead of expiration provisions, the 2001 AUMF and 2002 Iraq AUMF contain provisions which condition the exercise of such authority upon certain presidential determinations.
In any event, even in the absence of explicit expiration provisions—which declarations of war such as that at issue in Ludecke generally lacked—the Courts have continued to reiterate the underlying rule that the authority conferred by war authorization may be abrogated by presidential proclamation.[3] Notably, the Courts have looked to Ludecke in evaluating arguments over whether the hostilities authorized by the 2001 AUMF have been terminated.[4] These claims have arisen in the context of habeas corpus petitions brought by prisoners held by the U.S. military at Guantanamo Bay, Cuba challenging their continued law-of-war detention under the 2001 war authorization.
Citing Ludecke in 2010, the D.C. Circuit in Al-Bihani v. Obama observed that “[t]he determination of when hostilities have ceased is a political decision, and we defer to the Executive’s opinion on the matter, at least in the absence of congressional declaration purporting to terminate the war.” More recently in Al-Alwi v. Trump, the D.C. Circuit (citing Ludecke and Al-Bihani) observed regarding the 2001 AUMF that “[i]f the life of a statute conferring war powers on the Executive is defined by the existence of a war, Congress leaves the determination of when a war is concluded to the usual political agencies of the Government.” Therefore “in absence of Congressional definition of end of war, we defer to the Executive’s opinion on the matter.”
These cases reflect a background presumption that a presidential proclamation is a generally available mechanism for terminating the authority conferred by a declaration of war or authorization for the use of military force.
Terminating the 2002 Iraq AUMF
Beyond this presumption, in enacting the 2002 Iraq AUMF Congress explicitly granted the President the power to decide whether the stated predicates existed for the use of force. Specifically, it states that the authorization empowers the President to determine whether the use of “the Armed Forces of the United States” is “necessary and appropriate in order to” achieve the two specified objectives of defending U.S. national security from the threat posed by Iraq and enforcing relevant UN Security Council resolutions. Unlike the Formosa and Gulf of Tonkin Resolutions, which provided for a presidential determination for expiration of authority, the 2002 Iraq AUMF requires a presidential determination as a prerequisite for exercise of the authority.
The prerequisite for the exercise of the authority conferred by the 2002 Iraq AUMF has long been defunct. Decades after the toppling and death of Saddam Hussein and the conclusion of a Strategic Framework Agreement for a Relationship of Friendship and Cooperation with Iraq, the statutory purposes for which the use of military force were authorized by Congress are clearly no longer relevant. To the extent Iraq ever posed a threat to the national security of the United States (many of the premises of the 2002 Iraq AUMF enumerated in its preambular language are questionable at best) that is no longer the situation over twenty years later.
President Biden could reasonably determine that the purposes for using force specified in this war authorization are simply inapposite in 2024 through a formal proclamation declaring the conflict with Iraq over and terminating the authority conferred by the AUMF.
The operative language of such a proclamation might read:
Now, Therefore, I, Joseph R. Biden, President of the United States of America, do proclaim that hostilities and a state of war between the United States and Iraq are terminated as of [X Date]. I further determine for the purposes of the Authorization for Use of Military Force Against Iraq Resolution of 2002 (P.L. 107-243), it is no longer necessary and appropriate to use the Armed Forces of the United States in order to—
(1) defend the national security of the United States against the continuing threat posed by Iraq; and
(2) enforce all relevant United Nations Security Council resolutions regarding Iraq.
I therefore proclaim that the authority conferred on the President by P.L. 107-243 is terminated.
Limitations of a Presidential Proclamation
There may be limitations to terminating the authority of the 2002 Iraq AUMF via presidential proclamation.
Notwithstanding the endorsement of the mechanism by the courts in the Ludecke line of cases, only once has a U.S. president terminated a conflict (the U.S. Civil War) via unilateral proclamation. (Reportedly both the Trump and Biden administrations have however contemplated issuing an end of war “declaration” with respect to the Korean War, though the purpose of this document would be primarily diplomatic and not legal.)
Given this dearth of practice, there is therefore some doubt as to its enduring effectiveness. A subsequent president might seek to interpret their way around the proclamation to continue to use the purported authority of the resolution. And given the variety of mechanisms the judiciary uses to avoid weighing in on war powers issues (e.g. standing, ripeness, and the political question doctrine), it may be difficult to use the courts to push back on any such subsequent action, particularly in any timely fashion. Moreover, there is also the risk that a later president could simply rescind the proclamation or otherwise reactivate the authority conferred by the 2002 war authorization (although declaring the conditions for exercise of authority are met anew would likely strain credulity, at best).
Congressional repeal of the 2002 resolution remains the surest and most durable means of definitively annulling this authorization. Even if the President issued a termination proclamation, Congress should ultimately fulfill its own constitutional responsibilities by rescinding the resolution and not once again shirk its duties with respect to war and peace.
More fundamentally, even if a proclamation does effectively and permanently terminate the authority conferred by the 2002 Iraq AUMF, that resolution is but one source of authority for the U.S. President to wage imprudent war—including a conflict with Iran. Notably, when President Trump directed the 2020 strike against Iranian General Qassem Soleimani, OLC also cited the president’s authority under Article II of the Constitution as an independent legal basis for the action. Disarming the 2002 resolution would not alter the executive’s purported authority under Article II. That requires broader structural reform of the 1973 War Powers Resolution, such as that proposed the bipartisan National Security Powers Act and National Security Reform and Accountability Act.
Terminating the 2002 war authorization also would not affect the authority of the 2001 AUMF, the basis for the war on terror. Overhauling the 2001 authorization, including to eventually sunset the law, is a more complicated affair than terminating the 2002 resolution because the U.S. military still relies on it for ongoing, though greatly reduced, counter-terrorism operations, including detention at Guantanamo Bay, Cuba.
Further executive action would also be required to disavow other flawed executive branch legal opinions on presidential war powers that remain on the books. In addition to rescinding the Soleimani opinion, President Biden could direct the Department of Justice to withdraw a 1989 OLC opinion holding the President could “override” the UN Charter, as well as memos opining President Bush could have unilaterally waged both the war on terror and Iraq War even without congressional authorization. There is recent precedent for such a move. In 2009, the Department of Justice, citing President Obama’s Executive Order 13491, withdrew several Bush-era legal opinions relating to interrogation and detainee treatment (here and here).
A proclamation ending the Iraq War is therefore one necessary war powers reform measure, but hardly the only one.
Best Practical Option at the Moment
Despite these limitations, a presidential proclamation is the best near-term option to disarm the 2002 Iraq AUMF in the absence of congressional action.
Although a subsequent president might in principle rescind such a proclamation and seek to revive the Iraq War and the authority of the AUMF, it would likely be politically unattractive to do so and then publicly claim that this conflict continues. It is difficult to imagine either of President Biden’s likely successors wanting to publicly own the resurrection of the Iraq War.
Although the Biden administration could and should disavow the expansive, Iran-inclusive interpretations of the 2002 Iraq AUMF and rescind relevant legal memos, including OLC’s 2020 Soleimani opinion, a proclamation has a few comparative advantages beyond simply revoking prior legal opinions.
First, absent an act of termination, a subsequent administration could with little fanfare simply fall back upon the older, expansive interpretations of the 2002 Iraq AUMF in new legal opinions. There would be no need to issue another public proclamation and the reversion to Trump-era theories might only be disclosed belatedly in relatively obscure reports to Congress.
Second, though withdrawing flawed executive branch legal opinions is correct substantively in terms of good governance and facilitating the President’s constitutional obligation to “take Care that the Laws are faithfully executed,” it is likely to face bureaucratic resistance. Executive branch lawyers serving across administrations of both parties have played roles in formulating the broader, Iran-inclusive interpretations of the 2002 Iraq AUMF. Executive action to disavow those interpretations may thus face pushback from individuals personally invested in the soundness of these theories.
A proclamation avoids these potential pitfalls as it is public and is without prejudice to any prior executive branch interpretations of the war authorization.
Conclusion
A dominant theme of war powers scholarship and one I have emphasized previously is presidential overreach in war-making, all too often enabled by congressional underreach. Yet the courts have also endorsed a mechanism for unilateral presidential peacemaking: a presidential proclamation.
Given obstruction in the House of Representatives, the best option in principle for disposing of the 2002 Iraq AUMF—legislative repeal—is currently unavailable. In these circumstances, it is prudent for the White House to consider other lawful mechanisms for reducing the likelihood that this outdated war authorization is abused by a later commander-in-chief. A proclamation terminating the authority conferred by the resolution based on a determination that the specified objectives are now irrelevant is the best available tool.
As presidential candidate, Joe Biden pledged to end the “forever wars.” In his Oval Office address announcing his withdrawal from the 2024 presidential race, President Biden stated that the “United States is not at war.” A proclamation formally ending the Iraq War and abrogating its legal foundation would be a significant legacy in fulfilling these declarations.
[1] Specifically, the Obama administration later argued that
“[a]lthough the threat posed by Saddam Hussein’s regime in Iraq was the primary focus of the 2002 AUMF, the statute, in accordance with its express goals, has always been understood to authorize the use of force for the related dual purposes of helping to establish a stable, democratic Iraq and of addressing terrorist threats emanating from Iraq. After Saddam Hussein’s regime fell in 2003, the United States continued to take military action in Iraq under the 2002 AUMF to further these purposes, including action against AQI (now known as ISIL). Then, as now, that organization posed a terrorist threat to the United States and its partners and undermined stability and democracy in Iraq. Congress ratified this understanding of the 2002 AUMF by appropriating billions of dollars to support continued military operations in Iraq between 2003 and 2011.
Accordingly, the 2002 AUMF reinforces the authority for military operations against ISIL in Iraq and, to the extent necessary to achieve these purposes, elsewhere.”
[2] In 1956, the Court of Military Appeals concluded using a different totality of the circumstances analysis in U.S. v. Sanders that the Korean War had ended no later than June 4, 1955 and thus a U.S. soldier did not face the death penalty for falling asleep at his post during time of war.
[3] In their seminal 2005 article on congressional use of force authorizations, Curt Bradley and Jack Goldsmith observe in a footnote that “courts often defer to the President’s determinations concerning the status of military conflicts, see, e.g., Ludecke v. Watkins, 335 U.S. 160, 167-70 (1948) (deferring to the President’s determination that a state of war continued to exist with respect to Germany in World War II after Germany’s surrender); The Protector, 79 U.S. (12 Wall.) 700, 701-02 (1871) (deferring to presidential proclamations concerning when hostilities began and ended in the Civil War), and it is easy to imagine that such deference could affect judicial application of the AUMF.”
[4] The federal appeals courts that have addressed the “end of war” question specifically in connection with the 2002 Iraq AUMF have done so in relation to the Wartime Suspension of Limitations Act (WSLA). WLSA, as amended in 2008, provides that statute of limitations for certain federal offenses are suspended “until five years after the termination of hostilities as proclaimed by the Presidential proclamation, with notice to Congress, or by a concurrent resolution of Congress.” In 2012, the Fifth Circuit Court of Appeals concluded U.S. v. Pfulger that hostilities under the 2001 and 2002 AUMFs had not terminated for the purposes of WSLA because no U.S. president had issued the required formal proclamation terminating them. The 11th Circuit reached the same conclusion in 2015 in U.S. v. Frediani.