The 2001 AUMF: The one-way ratchet that irreversibly expanded presidential power

Despite Biden’s decision to end America’s longest war, we should not expect the 46th president to willingly relinquish the extraordinary national security powers that have accrued to his office since the terrorist attacks on September 11th, 2001.

Dr. Dorian Kantor is a political scientist, author, and professor of International Relations at Pontificia Universidad Javeriana. As a 2021 FES DC Media Fellow, he writes about U.S. foreign and national security policy.

Without a doubt, one of the most talked-about and, indeed, shameful episodes of the Biden presidency has been the U.S. Armed Forces’ chaotic and calamitous withdrawal from Afghanistan. Despite Biden’s decision to end America’s longest war, we should not expect the 46th president to willingly relinquish the extraordinary national security powers that have accrued to his office since the terrorist attacks on September 11th, 2001.

In this article, I will unpack the domestic legal bases of one element of the US government’s counterterrorism program – those statutory and constitutional foundations upon which national security policies are predicated. Although here I will focus on the use of drones or unmanned aerial vehicles (UAVs) to carry out lethal operations – also called targeted killings, extrajudicial executions, or assassinations; such policies also include the adoption of military commissions (rather than Article III courts) to try and convict terrorists; the indefinite detention of “enemy combatants” in Guantanamo Bay; and the domestic spying program formerly known as Stellar Wind or PRISM.

Far less discussed than the military’s messy departure from Afghanistan was President Biden’s swift retribution after the deadly ISIS-K attack on U.S. forces. The terrorist bombing at Hamid Karzai International Airport that claimed the lives of 13 service members and at least 160 civilians prompted the president to make a public demonstration of his resolve to rout out and punish those “who wish[] America harm.” Delivering his remarks on the night of the attacks, the president forewarned with steely resolve in his voice: “know this: We will not forgive. We will not forget. We will hunt you down and make you pay.” Making good on his promise, on August 29th, three days after the suicide attack, Biden authorized an MQ-9 Reaper drone to launch a Hellfire missile to destroy a “high-value target” in the city of Jalalabad. The target: a car and its occupants whom the military believed to be planners and facilitators of the Islamic State’s Afghan affiliate. Although the operation was a failure – it tragically killed ten civilians rather than a dangerous cell of ISIS fighters  –  this incident reveals an unsettling fact about the US government’s national security policymaking in the Global War on Terror (GWOT): the executive branch makes decisions in America’s “forever war” against terrorists with little-to-no statutory regulation, essentially in the absence of meaningful Congressional or judicial oversight, based (primarily) on a 20-year-old law which has served as a one-way ratchet that has irreversibly expanded presidential power.


The United States’ (largely) unregulated drone warfare

While the use of drones to carry out targeted killings is not the only area where the executive branch has a virtual carte blanche to protect the nation and national interests, it is by far the least regulated of the U.S. president’s counterterrorism tools. Of course, Joe Biden is not the first president to use UAVs in counterterrorism operations abroad. They were first employed as a weapon of the Global War on Terror during the George W. Bush administration, and they became the central tool of the Obama and Trump administrations’ warfighting arsenal. Whereas President Bush authorized merely 50 to 60 drone strikes, the number of UAV-executed attacks rose exponentially during Obama’s two terms in office to approximately 1,900 and skyrocketed under Trump’s single term to around 12,000. According to the UK-based Bureau of Investigative Journalism, between 9,000 and 17,000 have been killed in confirmed strikes, including between 900 and 2,200 civilians. Civilian deaths, however, are widely disputed, and, according to the non-profit transparency organization Airwars, the figure could be as high as 48,000.

Although most targeting operations go unnoticed by the vast majority of Americans, some have garnered substantial public attention. In 2013, for example, the government acknowledged that four U.S. citizens had been killed in drone strikes since President Obama took office in 2009, including Anwar al-Awlaki, the radical cleric and leader of an al Qaeda affiliate in Yemen, and his 16-year-old son. Perhaps the most famous of the UAV-executed lethal operations is the assassination in 2020 of Iranian General Qassim Suleimani, the powerful leader of the Quds Force of the Islamic Revolutionary Guards Corps. The Trump administration claimed that the killing of Suleimani was justified because Iran’s second most powerful figure was responsible for attacks on American bases and personnel in the Middle East. Despite the Pentagon’s assertion that the “strike was aimed at deterring future Iranian attack plans,” the operation was widely criticized as both illegal under the laws of armed conflict and as coming dangerously close to precipitating a cycle of escalation with unforeseen consequences in the region.


The Global War on Terror and the Office of Legal Counsel

Given the ubiquity of lethal drone strikes in the United States’ counterterrorism operations, the question arises: “Based on what authority do presidents carry out such targeted killings?” The answer to that question is multi-faceted and requires a bit of legal-historical context. First, we must become acquainted with the Office of Legal Counsel, or OLC for short, an “institution whose power is far greater than its prominence.” In brief, this obscure but influential office of the Department of Justice acts as a “mini Supreme Court” that has “final say on what the president and his agencies can and cannot legally do.”

As Jack Goldsmith, the former head of the OLC put it, President Bush primarily relied on his own constitutional authority to prosecute the post-9/11 War on Terror. In an effort spearheaded by then-Assistant Attorney General John Yoo, Bush’s OLC claimed constitutionally-derived legal authority for the president to protect national security through means such as the deployment of military force abroad, the establishment of an off-shore prison at Guantanamo Bay where the protections of the U.S. Constitution would not apply, and the use of enhanced interrogation techniques – some of which have been labeled as torture. As I argue in my forthcoming book Politics as Law, “the Bush OLC’s unilateralization of decision-making in the GWOT substantially depend[ed] on the President’s independent powers immune from congressional regulation.” Therefore, this “Commander-in-Chief override” served as OLC’s trump card with two distinct but interrelated purposes: (i) To bolster constitutionally-derived unilateral presidential authority in the realm of national security; and (ii) to nullify statutory limits on the president’s wartime authority to protect the nation from another terrorist attack of equal or greater magnitude than that perpetrated on September 11, 2001. By applying the Commander-in-Chief constitutional override, many of the Bush OLC’s opinions essentially did away with or dramatically narrowed the scope of domestic legislation such as the War Crimes Act (18 USC §2441) and the Torture Statute (18 USC §2440).


The AUMF goes to war: the Supreme Court’s decision in Hamdi

This brings us to the second, and most important, piece of the legal puzzle, the Authorization for the Use of Military Force (AUMF). The sweeping language of Public Law 107-40 (as it is titled in the U.S. Code) – passed just seven days after 9/11 – authorized the president

to use all 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, in order to prevent any future acts of international terrorism against the United States by such nations, organizations or persons.

In the 20 Bush-era legal opinions that I dissect in Politics as Law, the AUMF is one of the most often-cited legal authorities. Nevertheless, despite its broad and essentially unqualified grant of wartime authority, in the early years of the construction of the legal infrastructure that undergirded the GWOT, the Bush OLC largely relegated the AUMF to secondary status as “supporting legislation” relying instead on the president’s pre-existing constitutional powers:

Although Congress’s war powers under Article I, Section 8 of the Constitution empower Congress to legislate regarding the raising, regulation, and material support of the Armed Forces and related matters, rather than the prosecution of military campaigns, the AUMF indicates Congress’s endorsement of the President’s use of his constitutional war powers.

Moreover, in most of the pre-2004 legal opinions, the AUMF also functioned as a “defensive risk-management tool” – a shield from potential litigation against executive unilateralism. OLC’s logic was quite straightforward: were some executive actions found by a reviewing court to be in discord with any of Congress’s co-equal powers (and laws passed pursuant to those powers), the President would essentially have a free pass in the form of authorizing legislation. Indeed, as the Bush OLC pointed out in a legal memorandum regarding the president’s authority to use military force in Iraq, the administration deliberately sought to capitalize on the rally-around-the-flag effect after the 9/11 attacks when it obtained a blanket authorization from Congress to prosecute the Global War on Terror. Why did Bush seek such an authorization? Because constitutionally-based presidential power arguments often find themselves on thin ice before the federal judiciary, which is ultimately invested with the authority to decide on the legality of governmental action, including that of the executive branch.

The tendency to rely on the AUMF for legal authority in counterterrorism operations accelerated sharply following the Supreme Court’s decision in Hamdi v. Rumsfeld, a GWOT-related casein 2004 which involved the indefinite detention of U.S.-citizen enemy combatants in the Global War on Terror. The Bush OLC’s legal opinions utilized the AUMF a total of 29 times between 2001 and 2003, but in the first opinion alone issued after Hamdi, OLC referenced the AUMF 31 times. The Court’s overall favorable ruling in that case explains why. While the Court’s plurality declined to entertain the government’s original position that “the Executive[‘s] [] plenary authority to detain pursuant to Article II” was sufficient to overcome the statutory prohibition against the detention of U.S. citizens,[1] it did so because it found that a ruling on constitutional grounds was not necessary. Writing for the plurality, Justice O’Connor stated that the Court “[need] not reach [the constitutional] question” because the government’s alternative position that “Congress has in fact authorized Hamdi’s detention, through the AUMF” adequately resolved the matter at hand. O’Connor also concluded that the detention of enemy combatants in the Global War on Terror “is so fundamental and accepted an incident of war as to be an exercise of the ‘necessary and appropriate force’ Congress has authorized the President to use.” Therefore, in litigation before the Supreme Court, the AUMF fulfilled its function as a defensive risk management tool – a shield to protect the executive’s broad latitude to act independently from statutory limits in the AUMF-authorized War on Terror.

The year that Congress passed the Joint Resolution, Professor Michael Paulsen described the AUMF as “creat[ing] very nearly plenary presidential power to conduct the present war on terrorism, through the use of military and other means, against enemies both abroad and possibly even within the borders of the United States, as identified by the President, and without apparent limitations as to duration, scope, and tactics.” Nonetheless, in its zeal to aggrandize presidential power, independent of any authorizing legislation, the Bush OLC did not give the AUMF great emphasis in the early years of the construction of the GWOT legal architecture. By contrast, in the wake of the Supreme Court’s decision in Hamdi, OLC gave the AUMF a robust interpretation.

For the Bush OLC, the operative language in the Supreme Court’s decision was Justice O’Connor’s finding that the detention of enemy belligerents is a “fundamental (and accepted) incident of war.” Based on that wording, OLC declared that “[t]he Supreme Court’s interpretation of the AUMF in Hamdi v. Rumsfeld, confirms that Congress in the AUMF gave its express approval to the military conflict against al Qaeda and its allies and thereby to the President’s use of all traditional and accepted incidents of force in this current military conflict.” No longer did the AUMF appear as a backup or risk management argument; instead, it was front and center as the link connecting the Supreme Court’s endorsement of the President’s war powers and the executive’s plenary authority over the conduct of hostilities. At the same time, it also functioned as a legitimating device with vastly increased potency, since it “demonstrates [not only] Congress’s support for the President’s authority to protect the Nation,” but also “adheren[ce] to Justice O’Connor’s admonition that ‘a state of war is not a blank check for the President.’”

Based on this recalibrated argument, OLC concluded in its first post-Hamdi legal opinion that the AUMF had “confirmed and supplemented” the Commander in Chief’s power to unilaterally authorize the NSA’s intelligence gathering activities as a “fundamental incident of the use of military force.”[2] Thus, OLC moved the goalposts of the legal rationale. To greatly compress the argument: the AUMF authorized the detention of enemy combatants (including U.S. citizens), therefore wartime executive detention was legal. Since wartime detention was deemed a fundamental and accepted incident of war, by extension, other fundamental incidents of war were also legal, and they enjoyed the sanction of all three branches of government. Essentially, Hamdi rendered the constitutional override argument unnecessary and folded an extraordinarily wide range of Commander-in-Chief powers into the AUMF as long as they could labeled as “fundamental incidents of war.”[3] As the Bush OLC put it in the same legal opinion: “The Constitution gives the President the full authority necessary to carry out [the] solemn duty [to protect the American people], and he has made clear that he will use all authority available to him, consistent with the law [the AUMF], to protect the Nation.

In sum, Hamdi changed the war paradigm of counterterrorism from one unilaterally designed and implemented by the executive branch under President Bush, to one in which the blanket authorization that the administration sought in the immediate aftermath of 9/11 effectively stood in for a declaration of war endorsed by all three branches. Since 2004, based on the Supreme Court’s interpretation of the AUMF, the executive branch has wrung a wide range of wartime activities out of the congressional authorization. As Justice Robert Jackson wrote in dissent in the case Korematsu v. U.S. in 1944, “once a judicial opinion rationalizes” sweeping executive authority, it “lies about like a loaded weapon ready for the hand of any authority that can bring forward a plausible claim of an urgent need. Every repetition imbeds that principle more deeply in our law and thinking and expands it to new purposes.” Indeed, the AUMF has become such a loaded weapon as it continues to play a crucial role in the “forever war” against terrorism. In 2014, for example, the Obama administration construed the AUMF “to authorize extensive and ongoing use of military force against the Islamic States.” In 2020, nineteen years after the passage of the Joint Resolution, the Trump administration also relied on the AUMF to justify the targeted killing of Qassim Suleimani.


Repeal and replace?

Worried that Trump was bent on “rush[ing] to an unnecessary war” following Suleimani’s assassination, Congress passed Joint Resolution 68 whose purpose was to clarify that Public Law 107-40 did not “serve as specific statutory authorization for the use of force against Iran.” Although the bill failed to clear the two-thirds majority required to overcome the former president’s veto, Congress’ action indicates that – in the opinion of a bipartisan majority in both Houses – the executive branch has strayed too far from the 2001 AUMF’s original intent.

While President Biden has expressed openness to repealing the 2002 AUMF against Iraq (another statutory basis cited by the Trump administration for the targeting operation that killed Suleimani) and other “outdated authorizations for the use of military force,” one should not equate his administration’s openness on this score with willingness to relinquish the power that has accrued to the office of the president since 9/11. As the August 29 drone strike illustrates, Biden will flex his executive muscle – just like Trump and Obama did before him – if the occasion calls for it. Moreover, on the off chance that Congress would be inclined to repeal Pub Law 107-40 (which is not currently being considered in either house of the legislature), it is doubtful that future presidents would act with less sweeping authority in the realm of counterterrorism operations. This is due to what Professors Koh and Yoo call “quasi-constitutional custom:” a series of OLC legal opinions, a host of permissive court decisions, and extensive constitutional practice that, in the aggregate, have created a gloss on the functional separation of powers system of the United States – strengthening the hand of the president in the realm of national security and putting it well beyond the reach of statutory regulation.  


[1] §4001(a): “No citizen shall be imprisoned or otherwise detained by the United States except pursuant to an Act of Congress.”

[2] Elsewhere in the “NSA Memo,” OLC refers to warrantless foreign intelligence gathering as a “fundamental tool of warfare,” a “fundamental incident of waging war,” a “fundamental tool of war,” or a fundamental method of conducting wartime surveillance.”

[3]N.B., Jack Goldsmith’s explanation is that the altered application of the AUMF had to do with personnel change at the Office of Legal Counsel, which I do not disagree with, however, Hamdi’s ruling undeniable recalibrated the legal arguments available to OLC; see, Goldsmith, The Terror Presidency, 181.

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