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January 09, 2023

Targeting Terrorists with Drones

By: William C. Banks


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"Targeted killing” was not a term of art in national security law prior to the attacks of September 11, 2001. Since then, the term has been used with increasing frequency to refer to attacks by the United States on terrorist targets, especially by unmanned aerial vehicles (UAVs) or “drones.” For at least the last two decades, the United States has utilized UAVs for intelligence and combat purposes. Of the UAVs currently in the U.S. military arsenal, some are remotely piloted, some autonomous, and certain UAVs have attack capabilities, others do not. In the first decade after 9/11, U.S. drones became a critical weapon against terrorist targets in Afghanistan and other locations, including those not experiencing active hostilities. While the frequency and persistence of targeted killing by drone strikes have varied since 2011 and the future use of drones as attack weapons cannot be predicted with certainty, drone “crews have launched more missiles and killed more people than nearly anyone else in the [U.S.] military in the past decade.” Dave Philipps, The Unseen Scars of Those Who Kill Via Remote Control, N.Y. Times, Apr. 15, 2022. Undoubtedly, drones will remain a critical weapon in U.S. counterterrorism efforts in the coming years. 

Looking Back: Significant Events and Developments 2011-2021

On September 30, 2011, missiles from one or more U.S. drones struck the vehicle Anwar al-Aulaqi, or al-Awlaki, was riding in and killed him and at least three others. Al-Awlaki was a U.S. citizen who served as a propagandist for Al Qaeda in the Arabian Peninsula (AQAP). A Department of Justice White Paper, Lawfulness of a Lethal Operation Directed Against a U.S. Citizen Who Is a Senior Operational Leader of Al-Qa’ida or an Associated Force, Nov. 8, 2011, described the three conditions necessary “to conduct a lethal operation outside the United States against a U.S. citizen who is a senior, operational leader of al-Qa’ida … without violating the Constitution or [ ] federal statutes….”. Those three conditions can be summarized as (1) a determination of imminent threat, (2) infeasibility of capture, and (3) an operation consistent with the law of war. 

In 2013, President Barack Obama explained in Remarks by the President at the National Defense University (May 23, 2013):

For the record, I do not believe it would be constitutional for the government to target and kill any U.S. citizen — with a drone, or with a shotgun — without due process, nor should any President deploy armed drones over U.S. soil.

But when a U.S. citizen goes abroad to wage war against America and is actively plotting to kill U.S. citizens, and when neither the United States, nor our partners are in a position to capture him before he carries out a plot, his citizenship should no more serve as a shield than a sniper shooting down on an innocent crowd should be protected from a SWAT team….

I would have detained and prosecuted Awlaki if we captured him before he carried out a plot, but we couldn’t. And as President, I would have been derelict in my duty had I not authorized the strike that took him out.

Since 2011, UAVs have reportedly been used hundreds of times to fire on targets in Afghanistan, Iraq, Libya, Pakistan, Somalia, and Yemen. Senior Taliban, Al Qaeda, Islamic State of Iraq and Syria (ISIS), al-Shabab operatives have been killed in such attacks. But some number of civilians have also been killed, sometimes deliberately as unavoidable collateral damage and sometimes simply by mistake, including a 2021 “tragic mistake” that occurred during the withdrawal of U.S. personnel from Afghanistan.Vanessa Romo, No U.S. Troops Behind a Drone Strike That Killed Afghan Civilians Will Be Punished, NPR, Dec. 13, 2021. On August 29, 2021, the Pentagon claimed that it had successfully targeted an ISIS facilitator who posed an imminent threat at or near the Kabul airport. Several days later, the Pentagon acknowledged that it had instead mistakenly targeted Zemari Ahmadi, a longtime aid worker for a U.S.-based non-governmental organization. The strike killed him and nine other civilians, including several children. Letter from Senators Richard Durbin and Patrick Leahy to President Biden, Sept. 27, 2021; Christoph Koettl et al., The U.S. Military Said It Was an ISIS Safe House. We Found an Afghan Family Home, N.Y. Times, Sept. 28, 2021.

In 2013, President Obama announced U.S. Policy Standards and Procedures for the Use of Force in Counterterrorism Operations Outside the United States and Areas of Active Hostilities, May 22, 2013. The 2013 U.S. Policy Standards and Procedures provided criteria for targeting that focused on the seriousness of the threat the target posed to Americans. In 2016, the Obama administration elaborated on its drone targeting policies in the Report on the Legal and Policy Frameworks Guiding the United States’ Use of Military Force and Related National Security Operations (Dec. 2016) and asserted the following:

[A]n individual who is formally or functionally a member of an armed group against which the United States is engaged in an armed conflict is generally targetable. Determining that someone is a “functional” member of an armed group may include looking to, among other things, the extent to which that person performs functions for the benefit of the group that are analogous to those traditionally performed by members of a country’s armed forces; whether that person is carrying out or giving orders to others within the group; and whether that person has undertaken certain acts that reliably connote meaningful integration into the group. Id. at 19.

In 2017, President Donald Trump reportedly declared parts of Somalia an “area of active hostilities,” thus exempting them from the 2013 U.S. Policy Standards and Procedures. This change permitted the U.S. military to target for killing al-Shabab fighters in Somalia based strictly on their combatant status, instead of on the threat they posed to Americans. Charlie Savage & Eric Schmidt, Trump Eases Combat Rules in Somalia Intended to Protect Civilians, N.Y. Times, Mar. 30, 2017. In June 2017, a drone strike on an al-Shabab training camp in Somalia reportedly killed eight militants. Charlie Savage, Helene Cooper & Eric Schmidt, U.S. Strikes Shabab, Likely a First Since Trump Relaxed Rules for Somalia, N.Y. Times, June 11, 2017.

In October 2017, President Trump replaced the 2013 U.S. Policy Standards and Procedures with Principles, Standards, and Procedures for U.S. Direct Action Against Terrorist Targets. Robert Chesney, President Trump Ponders Changes to Lethal Force Policy Constraints: What You Need to Know, Lawfare, Sept. 22, 2017. The Trump administration did not make public its new standards and procedures for “direct action” operations, including drone strikes and commando raids outside of conventional war zones, but the new rules were disclosed in 2021 in response to Freedom of Information Act lawsuits brought by the New York Times and the American Civil Liberties Union. Charlie Savage, Trump’s Secret Rules for Drone Strikes Outside War Zones Are Disclosed, N.Y. Times, May 1, 2021. The 2017 policy permitted commanders in the field to decide whether to target suspects based on their status as members of a terrorist group, rather than on their conduct, as long as conditions specified in the new operating principles had been met. The “operating principles” stated that there should be “near certainty” that civilians “will not be injured or killed in the course of operations” but that “variations” could be made “where necessary” so long as commanders followed certain procedures. As Hina Shamsi, Director of the American Civil Liberties Union’s National Security Project described the 2017 policy, “the Trump rules served as open-ended authorization for the United States to kill virtually anyone it designates as a terrorist threat, anywhere in the world, without reference to the laws prohibiting extrajudicial killing under human rights law.” Hina Shamsi, Trump’s Secret Rules for Drone Strikes and Presidents’ Unchecked License to Kill, Just Security, May 3, 2021.

On January 3, 2020, U.S. forces launched a drone strike that killed General Qassem Soleimani, head of Iran’s Islamic Revolutionary Guard Corps–Quds, or Qods, Force (IRGC–QF), as he departed the Baghdad airport in Iraq. The U.S. had designated Iran a state sponsor of terrorism, and the IRGC–QF was and is its expeditionary force as well as being designated by the U.S. as a Specially Designated Global Terrorist and a Foreign Terrorist Organization. The IRGC–QF “spearheaded a closely coordinated campaign to equip the [Iraqi] Shi’a militia for proxy warfare,” targeting U.S. service members and others. Karcher v. Islamic Rep. of Iran, 396 F. Supp. 3d 12, 22-25 (D.D.C. 2019). The campaign killed at least 603 U.S. soldiers and severely injured many others. Kyle Rempfer, Iran Killed More US Troops in Iraq than Previously Known, Pentagon Says, Military Times, Apr. 4, 2019.

General Soleimani was not directly engaged in unlawful violence at the time of the strike but instead was reportedly driving to meet with the Iraqi Prime Minister. He was notorious for directing terrorist attacks in Iraq that targeted civilians, government officials, and U.S. and coalition forces since at least 2006. As described by Paul Ney, General Counsel, Department of Defense, DOD General Counsel Remarks at BYU Law School, Legal Considerations Related to the U.S. Air Strike Against Qassem Soleimani (Mar. 4, 2020),

In the weeks preceding the air strike against Soleimani, provocations against the United States intensified with a series of attacks by Iran-supported militias on U.S. personnel and property in Iraq. KH [Kata’ib Hizballah], the Qods Force-backed Shia militia group, fired rockets at bases in Iraq where U.S. forces are located. Between November 9 and December 9, 2019, Qods Force-backed militia groups fired rockets at the Qayyarah West Air Base, Al Asad Air Base, and the Baghdad Embassy complex. Then, on December 27, KH attacked the K-1 Air Base in Kirkuk, killing a U.S. contractor and injuring U.S. and Iraqi military personnel. In response, U.S. forces struck a number of KH installations in Iraq and Syria to degrade the group’s ability to launch additional attacks. Then, on December 31, KH and other Iran-backed militia groups organized a demonstration that turned violent at the U.S. Embassy in Baghdad, inflicting significant damage to U.S. property and imperiling U.S. lives.

It is unclear whether the Soleimani operation violated longstanding principles of international human rights law. That law’s “imminent danger” requirement, which justifies the use of lethal force in self-defense, might be given a more elastic construction to include a history of terrorist attacks that attests to both the ability and the intent to attack again and thus to legitimize the targeted killing of a suspected terrorist. David Kretzmer, Targeted Killing of Suspected Terrorists: Extra-Judicial Executions or Legitimate Means of Defence? 16 Eur. J. Int’l L. 171, 182 (2005). The targeted killing of Soleimani should also be assessed in light of the debates about status and conduct-based targeting. Mr. Ney justified Soleimani’s killing as follows:

Attacks against U.S. forces and interests were assessed to be highly likely to continue in the absence of a military response in self-defense to restore deterrence.

Moreover, the strike on January 2d was also consistent with the international law requirement that our measures in self-defense be “proportionate to the nature of the threat being addressed.” As DoD communicated to the public at the time, “General Soleimani was actively developing plans to attack American diplomats and service members in Iraq and throughout the region.” “He had orchestrated attacks on coalition bases in Iraq over the last several months,” and he also approved the demonstration that turned violent at the U.S. Embassy in Baghdad just two days earlier on December 31. Targeting the Iranian commander responsible for orchestrating, planning, and supporting recent attacks against the United States and planning new attacks was a proportionate response to the threat of such attacks.

Some have questioned whether another Iranian armed attack against the United States was “imminent” at the time of the strike targeting Soleimani. This is a red herring, as the saying goes. Under international law, an imminent attack is ​not​ a necessary condition for resort to force in self-defense in this circumstance because armed attacks by Iran already had occurred and were expected to occur again.

Of course, although such analysis was not necessary in this case given this recent history of past attacks, the ​threat​ of an imminent armed attack can also justify a resort to force under international law. Ney, supra.

On July 16, 2021, the Justice Department released a heavily redacted copy of a March 2020 Office of Legal Counsel (OLC) memorandum that provided the legal rationale for the drone strike that killed General Soleimani. January 2020 Airstrike in Iraq Against Qassem Soleimani, 44 Op. O.L.C. __ (2020). The OLC concluded that “given the targeted scope of the mission, the available intelligence, and the efforts to avoid escalation ... the President could reasonably determine that the nature, scope, and duration of hostilities directly resulting from the strike against Soleimani would not rise to the level of war for constitutional purposes,” id. at 20, meaning that specific approval from Congress was not required. In addition to the President’s authority under Article II of the United States Constitution, the OLC also found authority for the strike in the 2002 Authorization for the Use of Military Force (AUMF), which authorized the President to use force “as he determines to be necessary and appropriate in order to . . . defend the national security of the United States against the continuing threat posed by Iraq.” Id. (emphasis added in OLC memo). The OLC memorandum reasoned that the use of force “may address threats also posed by militias, terrorist groups, or other armed groups in Iraq.” Id. Thus, intelligence indicating that the Quds Force would continue to undermine stability in Iraq, along with the narrow tailoring of the air strike to Soleimani’s presence in Iraq and his support and direction of militias operating in Iraq further brought the U.S. strike within the authority provided by the 2002 AUMF. Id. Editor’s Note: for analysis of the Soleimani killing under international humanitarian law, see United Nations, Office of the High Commissioner for Human Rights, Report of the Special Rapporteur on Extrajudicial, Summary or Arbitrary Executions, Use of Armed Drones for Targeted Killings (Aug. 15, 2020)

Looking Ahead: Future Challenges in Targeting with Drones

On January 20, 2021, President Joe Biden suspended the prior administration’s drone targeting rules and replaced them with an interim policy that requires White House approval for strikes outside of the specified active war zones in Afghanistan, Iraq, and Syria. As the Biden administration was finalizing a new policy for drone strikes outside conventional war zones, the abrupt collapse of the Afghan government in August 2021 interrupted the process. Reportedly, the new policy would return to centralized interagency vetting of proposed strikes in nations where such operations are rare, but, for places where drone strikes are routine, “country plans” would set policy goals and targeting standards, leaving commanders in the field latitude to carry out individual strikes. Charlie Savage, Afghanistan Collapse and Strikes in Somalia Raise Snags for Drone Warfare Rules, N.Y. Times, Aug. 28, 2021.

Until the sudden change in circumstances in Afghanistan, the Biden administration envisioned drone strikes against Al Qaeda or ISIS targets there with the consent of the Afghan government and the presumed neutrality of the Taliban. With the Taliban now in charge, the future of U.S. counterterrorism operations in Afghanistan, including drone strikes against terrorist targets, is unclear. Meanwhile, the military’s United States Africa Command carried out three drone strikes targeting al-Shabab personnel in Somalia in July and August 2021. The strikes were conducted without White House approval on the grounds that they were undertaken in defense of Somalian government forces who were fighting al-Shabab. Savage, id.

As of January 2022, a new policy for U.S. drone strikes of terrorist targets had not been announced. After the U.S. withdrawal from Afghanistan, President Biden spoke of “over-the-horizon capabilities, which means we can strike terrorists and targets without American boots on the ground or very few, if needed.” Remarks by President Biden on the End of the War in Afghanistan (Aug. 31, 2021). Two Army officers who had counterterrorism responsibilities in Afghanistan have proposed “near certainty” as the standard for “both target identification and protection of civilians” and the “best way to balance the risks inherent in a lethal, over-the-horizon counterterrorism campaign.” Brian Hausle & Matt Montazzoli, Finding the Appropriate Balance of Risk in Over-the-Horizon Strikes, Lawfare, Nov. 21, 2021. Whatever the standards and procedures for targeting terrorists with drones, they need to be articulated because, with or without them, there is little doubt that the U.S. military will continue to employ drones to target terrorists with lethal results.

William Banks

Chair, Standing Committee on Law and National Security

Board of Advisors Distinguished Professor Emeritus, College of Law/Maxwell School of Citizenship and Public Affairs, Syracuse University. Editor, Journal of National Security Law and Policy; founder of the Institute for National Security and Counterterrorism (now the Institute for Security Policy and Law) at Syracuse. Former Interim Dean, Syracuse University Law School and Special Counsel, U.S. Senate Judiciary Committee.

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The views expressed herein represent the opinions of the authors. They have not been approved by the House of Delegates or the Board of Governors of the American Bar Association and, accordingly, should not be construed as representing the position of the Association or any of its entities. Nothing contained in this publication is to be considered as the rendering of legal advice for specific cases, and readers are responsible for obtaining such advice from their own legal counsel. This publication is intended for educational and informational purposes only.

The material in all ABA publications is copyrighted and may be reprinted by permission only. Request reprint permission here.