b'Targeted Airstrikes Against the Islamic\nState of Iraq and the Levant\nThe President had the constitutional authority to order targeted airstrikes in Iraq against\nthe Islamic State of Iraq and the Levant without prior congressional authorization.\nThe President had reasonably determined that these military operations would further\nsufficiently important national interests. A combination of three relevant national interests\xe2\x80\x94protecting American lives and property; assisting an ally or strategic partner\nat its request; and protecting endangered populations against humanitarian atrocities,\nincluding possible genocide\xe2\x80\x94supported the President\xe2\x80\x99s constitutional authority to\norder the operations without prior congressional authorization.\nThe anticipated nature, scope, and duration of the military operations did not rise to the\nlevel of a \xe2\x80\x9cwar\xe2\x80\x9d within the meaning of the Declaration of War Clause.\nDecember 30, 2014\n\nMEMORANDUM OPINION FOR THE COUNSEL TO THE PRESIDENT\nOn August 8, 2014, United States Armed Forces commenced targeted\nairstrikes in Iraq against the terrorist group the Islamic State of Iraq and\nthe Levant (\xe2\x80\x9cISIL\xe2\x80\x9d). Before the strikes began, our Office advised you that\nthe President had the constitutional authority to order these military\noperations because he had reasonably determined that they would further\nsufficiently important national interests, and because their anticipated\nnature, scope, and duration were sufficiently limited that prior congressional approval was not constitutionally required. This memorandum\nmemorializes and explains the basis for our advice. 1\n\n1 This advice was provided before the President decided to rely on statutory authority\nfor military operations against ISIL. We accordingly do not address in this opinion\nwhether the targeted military actions discussed herein were authorized by any statute. We\nfurther note that on September 10, 2014, after the advice memorialized in this opinion had\nalready been provided, the President announced a new \xe2\x80\x9ccomprehensive and sustained\ncounterterrorism strategy\xe2\x80\x9d to address the threat posed by ISIL that, among other things,\ncalled for a \xe2\x80\x9csystematic campaign of airstrikes\xe2\x80\x9d against the organization in Iraq and, if\nnecessary, Syria. Office of the Press Secretary, The White House, Statement by President\nObama on ISIL (Sept. 10, 2014), https://obamawhitehouse.archives.gov/the-press-office/\n2014/09/10/statement-president-isil-1. You have not asked us to consider in this opinion,\nand we do not address, the President\xe2\x80\x99s authority to implement this new strategy. We also\ndo not consider whether the discrete military operations discussed in this opinion would\n\n82\n\n\x0cTargeted Airstrikes Against the Islamic State of Iraq and the Levant\n\nI.\nThe conflict that led to the airstrikes discussed in this opinion has its\norigins in the most recent Iraq War. In 2002, in response to concerns that\nSaddam Hussein\xe2\x80\x99s regime might be developing and stockpiling weapons\nof mass destruction and aiding and harboring terrorists, Congress authorized the President to use military force against the threat posed by Iraq.\nSee Authorization for Use of Military Force Against Iraq Resolution of\n2002, Pub. L. No. 107-243, 116 Stat. 1498 (\xe2\x80\x9cIraq AUMF\xe2\x80\x9d); Raymond W.\nCopson, Cong. Research Serv., RL31715, Iraq War: Background and\nIssues Overview 1\xe2\x80\x932 (Apr. 22, 2003) (\xe2\x80\x9cIraq War: Background and Issues\nOverview\xe2\x80\x9d). On March 19, 2003, after diplomatic efforts to resolve these\nconcerns failed, the United States began aerial attacks in Iraq. See Iraq\nWar: Background and Issues Overview at 4. U.S. and British ground forces\nentered Iraq the next day, id., and several weeks later, Saddam Hussein\xe2\x80\x99s\nregime fell, Kenneth Katzman, Cong. Research Serv., RS21968, Iraq:\nPolitics, Governance, and Human Rights 1 (Aug. 12, 2014) (\xe2\x80\x9cIraq: Politics, Governance, and Human Rights\xe2\x80\x9d). After the fall of the regime, a new\nIraqi government was formed, and U.S. and other coalition forces remained in Iraq to help secure and stabilize the country. See id. Over the\nnext few years, however, as sectarian divisions in Iraqi society deepened,\nsee id. at 4, the terrorist group Al-Qaeda in Iraq\xe2\x80\x94Al-Qaeda\xe2\x80\x99s affiliate in\nIraq and the primary source of armed opposition to the new Iraqi government and U.S. forces\xe2\x80\x94intensified its operations and expanded its\nreach, see Kenneth Katzman, Cong. Research Serv., RL32217, Al Qaeda\nin Iraq: Assessment and Outside Links 1, 10\xe2\x80\x9311 (Aug. 15, 2008); Bradley\nGraham, Zarqawi \xe2\x80\x9cHijacked\xe2\x80\x9d Insurgency, Wash. Post, Sept. 28, 2005, at\nA17. In 2006, Al-Qaeda in Iraq renamed itself the Islamic State of Iraq\n(\xe2\x80\x9cISI\xe2\x80\x9d). See Kenneth Katzman et al., Cong. Research Serv., R43612, Iraq\nCrisis and U.S. Policy 8 (Aug. 8, 2014) (\xe2\x80\x9cIraq Crisis and U.S. Policy\xe2\x80\x9d).\nViolence continued to escalate and, by early 2007, had become widespread and severe. See Nominations Before the Senate Armed Services\nCommittee: Hearings Before the S. Comm. on Armed Servs., 110th Cong.\n5\xe2\x80\x938 (2007) (statement of Lt. Gen. David H. Petraeus). The United States\nhave been within the President\xe2\x80\x99s constitutional authority if they had been ordered pursuant to the newly announced strategy, rather than for the more limited missions for which\nthey were actually ordered.\n\n83\n\n\x0c38 Op. O.L.C. 82 (2014)\n\nresponded with a surge of nearly 30,000 troops. See Iraq: Politics, Governance, and Human Rights at 4. Over the course of 2007 and 2008, in\nthe wake of the surge, sectarian violence in Iraq dropped dramatically.\nSee Stephen Biddle et al., Testing the Surge: Why Did Violence Decline\nin Iraq in 2007?, 37 Int\xe2\x80\x99l Sec. 7 (Summer 2012).\nIn 2008, the United States and Iraq signed a Strategic Framework\nAgreement for a Relationship of Friendship and Cooperation Between the\nUnited States of America and the Republic of Iraq (\xe2\x80\x9cStrategic Framework\nAgreement\xe2\x80\x9d or \xe2\x80\x9cAgreement\xe2\x80\x9d), which recognized that cooperation between\nthe two countries would \xe2\x80\x9cimprove and strengthen security and stability in\nIraq and the region.\xe2\x80\x9d Strategic Framework Agreement at 2 (Nov. 17,\n2008), https://www.state.gov/documents/organization/122076.pdf. Among\nits many provisions, the Agreement stated that the United States and Iraq\nwould \xe2\x80\x9ccontinue to foster close cooperation concerning defense and\nsecurity arrangements without prejudice to Iraqi sovereignty over its land,\nsea, and air territory.\xe2\x80\x9d Id. at 3. The United States began to reduce its military presence in Iraq in 2009, and in December 2011, the last U.S. troops\nleft the country. See Iraq: Politics, Governance, and Human Rights at 8;\nTim Arango & Michael S. Schmidt, Last Convoy of American Troops\nLeaves Iraq, Marking a War\xe2\x80\x99s End, N.Y. Times, Dec. 19, 2011, at A6. In\nannouncing this withdrawal, President Obama explained that the United\nStates was \xe2\x80\x9cmoving into a new phase in [its] relationship\xe2\x80\x9d with Iraq, \xe2\x80\x9can\nequal partnership based on mutual interests and mutual respect.\xe2\x80\x9d Office\nof the Press Secretary, The White House, Remarks by the President on\nEnding the War in Iraq (Oct. 21, 2011), https://obamawhitehouse.\narchives.gov/the-press-office/2011/10/21/remarks-president-ending-wariraq.\nAfter U.S. military forces had left Iraq in 2011, the long-standing sectarian and ethnic divisions in the country again widened, leading to increased discontent and unrest. See Iraq: Politics, Governance, and Human\nRights at 15\xe2\x80\x9319. During this period, Sunni extremists, including ISI,\ngained strength. See id. In April 2013, after having expanded into Syria,\nISI adopted the name ISIL. 2 See Iraq Crisis and U.S. Policy at 8, 11. ISIL\n2 ISIL is also sometimes referred to as the \xe2\x80\x9cIslamic State of Iraq and Syria,\xe2\x80\x9d or \xe2\x80\x9cISIS.\xe2\x80\x9d\nThis opinion refers to the group as \xe2\x80\x9cISIL\xe2\x80\x9d hereafter, including in references to the group\nfollowing its decision to change its name to the \xe2\x80\x9cIslamic State.\xe2\x80\x9d See infra p. 86.\n\n84\n\n\x0cTargeted Airstrikes Against the Islamic State of Iraq and the Levant\n\nsoon launched a series of attacks in Iraq. See id. at 7\xe2\x80\x939. In December\n2013, aided by Sunni citizens and tribal fighters dissatisfied with the\nfailure of Iraq\xe2\x80\x99s Shiite-dominated leadership to create an inclusive government, ISIL attacked the Iraqi cities of Ramadi and Fallujah, ultimately\ngaining control of Fallujah despite an Iraqi counteroffensive. See Iraq:\nPolitics, Governance, and Human Rights at 18. Then, in June 2014, ISIL\nlaunched a major offensive in Iraq and, assisted by the widespread surrender and withdrawal of the Iraqi Security Forces (\xe2\x80\x9cISF\xe2\x80\x9d) and an influx of\nfighters from Syria, captured Mosul, Iraq\xe2\x80\x99s second largest city, and large\nareas of the provinces of Nineveh and Salahuddin. See id. at 19; Rod\nNordland, Sunnis in Iraq Make Some Gains in Fighting in the North and\nWest, N.Y. Times, June 22, 2014, at A7. ISIL militants thereafter rapidly\nexpanded their control over northwestern areas of Iraq, capturing key\ncities and attacking Iraq\xe2\x80\x99s largest oil refinery. See Iraq: Politics, Governance, and Human Rights at 19\xe2\x80\x9320. Within a week of Mosul\xe2\x80\x99s fall, ISIL\nreached the outskirts of Baquabah, thirty-eight miles from Baghdad,\nprompting fear that the capital too would fall. See Iraq Crisis and U.S.\nPolicy at 1. ISIL militants also advanced toward the Haditha Dam, situated about 120 miles northwest of Baghdad on the Euphrates River, raising\nthe prospect of catastrophic flooding if the dam were to fail. See Alissa J.\nRubin & Rod Nordland, As Calls for New Iraqi Government Grow, Militants Advance Toward Strategic Dam, N.Y. Times, June 25, 2014, at A10.\nIn the course of its advance, ISIL looted banks of millions of dollars,\nseized a substantial amount of U.S.-supplied military equipment, and\nfreed prisoners. See Iraq Crisis and U.S. Policy at 1. Its tactics were\nbrutal: it executed innocent civilians, performed mass executions of ISF\nmembers, kidnapped and raped women and children, and displaced hundreds of thousands of Iraqis from their homes. See Office of the High\nCommissioner for Human Rights & U.N. Assistance Mission for Iraq\n(UNAMI) Human Rights Office, Report on the Protection of Civilians in\nthe Non-International Armed Conflict in Iraq: 5 June\xe2\x80\x935 July 2014, at 7\xe2\x80\x93\n13, https://www.ohchr.org/Documents/Countries/IQ/UNAMI_OHCHR_\nPOC%20Report_FINAL_18July2014A.pdf.\nIn remarks on June 19, 2014, President Obama declared ISIL \xe2\x80\x9ca threat\nto the Iraqi people, to the region, and to U.S. interests.\xe2\x80\x9d Office of the\nPress Secretary, The White House, Remarks by the President on the\nSituation in Iraq (June 19, 2014), https://obamawhitehouse.archives.gov/\n85\n\n\x0c38 Op. O.L.C. 82 (2014)\n\nthe-press-office/2014/06/19/remarks-president-situation-iraq. He stated\nthat \xe2\x80\x9c[i]t is in [the] national security interests [of the United States] not to\nsee an all-out civil war inside of Iraq,\xe2\x80\x9d and to \xe2\x80\x9cmak[e] sure that we don\xe2\x80\x99t\nhave a safe haven\xe2\x80\x9d in Iraq \xe2\x80\x9cthat continues to grow for ISIL and other\nextremist jihadist groups who could use that as a base of operations for\nplanning and targeting ourselves, our personnel overseas, and eventually\nthe homeland.\xe2\x80\x9d Id. The President then announced that he had positioned\nadditional U.S. military assets in the region and \xe2\x80\x9cw[ould] be prepared to\ntake targeted and precise military action\xe2\x80\x9d if and when he determined that\n\xe2\x80\x9cthe situation on the ground require[d] it.\xe2\x80\x9d Id. In light of the growing\nthreat from ISIL, the President also dispatched U.S. military personnel to\nIraq three times in June to, among other things, provide support and\nsecurity for U.S. embassy personnel in Baghdad and establish joint\noperations centers with Iraqi forces. 3\nOn June 29, ISIL changed its name to the \xe2\x80\x9cIslamic State\xe2\x80\x9d and declared\nthat it had established an Islamic \xe2\x80\x9ccaliphate\xe2\x80\x9d extending from the Aleppo\nprovince in Syria to the Diyala province in Iraq. Iraq Crisis and U.S.\nSee Office of the Press Secretary, The White House, Text of a Letter from the President to the Speaker of the House of Representatives and the President Pro Tempore of the\nSenate (June 16, 2014), https://obamawhitehouse.archives.gov/the-press-office/2014/06/\n16/text-letter-president-speaker-house-representatives-and-president-pro-te (authorizing\nthe deployment of 275 troops \xe2\x80\x9cto provide support and security for U.S. personnel and the\nU.S. Embassy in Baghdad\xe2\x80\x9d); Office of the Press Secretary, The White House, Letter from\nthe President\xe2\x80\x94War Powers Resolution Letter Regarding Iraq (June 26, 2014), https://\nobamawhitehouse.archives.gov/the-press-office/2014/06/26/letter-president-war-powersresolution-letter-regarding-iraq (authorizing the deployment of 300 additional troops \xe2\x80\x9cto\nassess how we can best train, advise, and support Iraqi security forces and to establish\njoint operations centers with Iraqi security forces to share intelligence and coordinate\nplanning to confront the threat posed by ISIL\xe2\x80\x9d); Office of the Press Secretary, The White\nHouse, Letter from the President\xe2\x80\x94War Powers Resolution Letter Regarding Iraq (June\n30, 2014), https://obamawhitehouse.archives.gov/the-press-office/2014/06/30/letterpresident-war-powers-resolution-letter-regarding-iraq (authorizing the deployment of 200\nadditional troops \xe2\x80\x9cto reinforce security at the U.S. Embassy, its support facilities, and the\nBaghdad International Airport\xe2\x80\x9d). In early September, the President authorized the deployment of an additional 350 U.S. military personnel \xe2\x80\x9cto provide support and security for\nU.S. personnel and the U.S. Embassy in Baghdad.\xe2\x80\x9d Office of the Press Secretary, The\nWhite House, Letter from the President\xe2\x80\x94War Powers Resolution Regarding Iraq (Sept. 5,\n2014), https://obamawhitehouse.archives.gov/the-press-office/2014/09/05/letter-presidentwar-powers-resolution-regarding-iraq.\n3\n\n86\n\n\x0cTargeted Airstrikes Against the Islamic State of Iraq and the Levant\n\nPolicy at 8. The declaration named ISIL\xe2\x80\x99s leader Abu Bakr al Baghdadi as\nImam and \xe2\x80\x9c[C]aliph.\xe2\x80\x9d Id. In territories they controlled, ISIL militants\nintensified a campaign of persecution against non-Sunni religious groups\nand ethnic minorities, including Shiites, Christians, and Yezidis, an ancient and long-persecuted religious sect. See Alissa J. Rubin, ISIS Expels\nLast Iraqi Christians from Mosul, N.Y. Times, July 19, 2014, at A4;\nLoveday Morris, Islamic State Forces Take an Iraqi Town, Wash. Post,\nAug. 4, 2014, at A9; Press Statement, Office of Press Relations, U.S.\nDep\xe2\x80\x99t of State, ISIL Claims Massacre in Tikrit (June 15, 2014) (\xe2\x80\x9cState\nDepartment June 15 Press Statement\xe2\x80\x9d), https://2009-2017.state.gov/r/pa/\nprs/ps/2014/06/227605.htm. Journalists reported that when ISIL militants\nswept through Sinjar, a town in northwestern Iraq with a large Yezidi\npopulation, they \xe2\x80\x9cset about their method of conquest, which is as familiar\nas it is brutal: They destroyed a Shiite shrine, executed resisters, overran\nlocal security forces and hoisted the black flag of [ISIL] above government buildings.\xe2\x80\x9d Tim Arango, Sunni Extremists in Iraq Seize 3 Towns\nFrom Kurds and Threaten Major Dam, N.Y. Times, Aug. 4, 2014, at A7.\nYezidi residents reported witnessing kidnappings and executions of members of their sect. See id. Tens of thousands of residents fled to the northern Kurdish region of Iraq, while thousands of others, largely from the\nYezidi community, sought refuge on Mount Sinjar, where they were\nbesieged by ISIL militants. See Alissa J. Rubin, For Refugees on Mountain, \xe2\x80\x9cNo Water, No Nothing,\xe2\x80\x9d N.Y. Times, Aug. 10, 2014, at A1. Those\ntrapped on the mountain confronted a choice between descending into\nareas controlled by the militants and facing likely death, or remaining on\nthe mountain without sufficient food, water, or medicine. See Loveday\nMorris, Cornered on Mountain, Minority-Sect Iraqis Are Dying of Thirst,\nWash. Post, Aug. 6, 2014, at A10. The U.N. Special Representative of the\nSecretary-General for Iraq warned that \xe2\x80\x9c[a] humanitarian tragedy [wa]s\nunfolding in Sinjar.\xe2\x80\x9d UN News Centre, UN Warns of \xe2\x80\x9cHumanitarian\nTragedy\xe2\x80\x9d as Militants Seize Town in Northern Iraq (Aug. 3, 2014); see\nalso Security Council, Press Statement on Iraq, U.N. Press Release\nSC/11509 (Aug. 5, 2014) (\xe2\x80\x9cSecurity Council August 5 Press Release\xe2\x80\x9d)\n(expressing \xe2\x80\x9cdeep concern\xe2\x80\x9d about the thousands of Iraqis, many from the\nYezidi community, displaced by ISIL and \xe2\x80\x9cin urgent need of humanitarian\nassistance\xe2\x80\x9d). Days after the siege on Mount Sinjar began, the U.N. Security Council \xe2\x80\x9ccall[ed] on the international community to support the Gov87\n\n\x0c38 Op. O.L.C. 82 (2014)\n\nernment and people of Iraq and to do all it c[ould] to help alleviate the\nsuffering of the population affected by the current conflict in Iraq.\xe2\x80\x9d Security Council, Press Statement on Iraq, U.N. Press Release SC/11515 (Aug.\n7, 2014) (\xe2\x80\x9cSecurity Council August 7 Press Release\xe2\x80\x9d).\nBy early August 2014, ISIL militants had seized control of additional\ntowns in northern Iraq and were advancing towards the city of Erbil,\nwhere numerous American diplomats, military advisers, and other citizens were based. See Helene Cooper et al., Obama Allows Airstrikes\nAgainst Iraq Rebels, N.Y. Times, Aug. 8, 2014, at A1; Iraq: Politics,\nGovernance, and Human Rights at 19. ISIL militants had also seized\ncontrol of the Mosul Dam, Iraq\xe2\x80\x99s largest, from Kurdish forces. See Tim\nArango, Jihadists Rout Kurds in North and Seize Strategic Iraqi Dam,\nN.Y. Times, Aug. 8, 2014, at A1 (\xe2\x80\x9cJihadists Rout Kurds\xe2\x80\x9d). ISIL\xe2\x80\x99s seizure\nof the Mosul Dam raised concerns because, as a 2007 report by the Army\nCorps of Engineers explained, the Mosul Dam rests on a \xe2\x80\x9cvery poor\xe2\x80\x9d\nfoundation of water-soluble rock and soil and therefore \xe2\x80\x9cdemand[s]\nextraordinary engineering measures to maintain\xe2\x80\x9d its \xe2\x80\x9cstructural integrity\nand operating capability.\xe2\x80\x9d Julie R. Kelley et al., U.S. Army Corps of\nEngineers, ERDC TR-07-10, Geologic Setting of Mosul Dam and Its\nEngineering Implications 2 (Sept. 2007) (\xe2\x80\x9cGeologic Setting of Mosul\nDam\xe2\x80\x9d). Consistent with that report, the United States had advised Iraq\nthat an extensive grouting program should be continued to \xe2\x80\x9cmitigat[e] the\nrisk at Mosul Dam,\xe2\x80\x9d explaining that \xe2\x80\x9ca catastrophic failure\xe2\x80\x9d of the dam\nwould \xe2\x80\x9cresult in flooding along the Tigris River all the way to Baghdad,\xe2\x80\x9d\nand, in a worst case scenario, \xe2\x80\x9ca f lood wave 20 meters [65 feet] deep at\nthe city of Mosul,\xe2\x80\x9d threatening \xe2\x80\x9csignificant loss of life and property.\xe2\x80\x9d\nLetter for Nouri al-Maliki, Prime Minister, Republic of Iraq, from General David H. Petraeus, U.S. Army, and Ambassador Ryan C. Crocker,\nUnited States Embassy, Baghdad (May 3, 2007), reprinted in Office of\nthe Special Inspector General for Iraq Reconstruction, Relief and Reconstruction Funded Work at Mosul Dam, SIGIR PA-07-105, app. D (Oct.\n29, 2007) (\xe2\x80\x9cMosul Dam Letter\xe2\x80\x9d). A later article by an Army Corps official estimated that the dam\xe2\x80\x99s failure \xe2\x80\x9ccould lead to as many as 500,000\ncivilian deaths by inundating the cities of Mosul and Baghdad under\nwater.\xe2\x80\x9d Amanda Ellison, An Unprecedented Task, 63 Int\xe2\x80\x99l Water Power\n& Dam Construction 50, 50\xe2\x80\x9351 (Sept. 2011).\n88\n\n\x0cTargeted Airstrikes Against the Islamic State of Iraq and the Levant\n\nISIL militants also continued to battle ISF and allied tribal forces for\ncontrol of the Haditha Dam. See Jihadists Rout Kurds, N.Y. Times,\nAug. 8, 2014, at A1. According to press accounts, releasing water from or\ndestroying that dam could unleash walls of water that could travel hundreds of miles down the Euphrates River, cripple the electricity supply in\nIraq, and potentially flood the southern regions of Baghdad. See Nigel\nWilson, Middle East Water Wars: Why Islamic State Wants Iraq\xe2\x80\x99s Dams,\nInt\xe2\x80\x99l Bus. Times, Aug. 5, 2014, https://www.ibtimes.co.uk/middle-eastwater-wars-why-islamic-state-wants-iraqs-dams-1459895; Doug Struck,\nThe Coolest Posting in a Hot War Zone, Wash. Post, Aug. 8, 2004, at\nA17.\nIn response to these developments (and subsequent developments described below), the United States began a series of targeted airstrikes\nagainst ISIL positions in Iraq, each directed at either protecting Americans from an impending threat or preventing a humanitarian catastrophe,\nand each also undertaken in part to assist Iraq, at its request, in combating\nISIL.\nAirstrikes Near Erbil and Mount Sinjar. On August 7, 2014, President\nObama announced that he had authorized two military operations in Iraq:\n\xe2\x80\x9ctargeted airstrikes to protect our American personnel, and a humanitarian\neffort to help save thousands of Iraqi citizens who are trapped on a mountain without food and water and facing almost certain death.\xe2\x80\x9d Office of the\nPress Secretary, The White House, Statement by the President (Aug. 7,\n2014) (\xe2\x80\x9cPresident Obama August 7 Statement\xe2\x80\x9d), https://obamawhitehouse.\narchives.gov/the-press-office/2014/08/07/statement-president. In the first\noperation, U.S. military forces \xe2\x80\x9cconducted targeted airstrikes against\nterrorist forces outside the city of Erbil to prevent them from advancing\non the city and to protect our American diplomats and military personnel.\xe2\x80\x9d Office of the Press Secretary, The White House, Statement by the\nPresident on Iraq (Aug. 9, 2014) (\xe2\x80\x9cPresident Obama August 9 Statement\xe2\x80\x9d), https://obamawhitehouse.archives.gov/the-press-office/2014/08/\n07/statement-president. In the second operation, U.S. forces conducted\nairdrops of food and water on Mount Sinjar and targeted airstrikes\nagainst ISIL militants besieging the mountain in order to protect the\nstranded Yezidis and assist in their escape. See Office of the Press Secretary, The White House, Statement by the President (Aug. 14, 2014)\n(\xe2\x80\x9cPresident Obama August 14 Statement\xe2\x80\x9d), https://obamawhitehouse.\n89\n\n\x0c38 Op. O.L.C. 82 (2014)\n\narchives.gov/the-press-office/2014/08/14/statement-president; President\nObama August 9 Statement. The President explained:\nWhen we face a situation like we do on that mountain\xe2\x80\x94with innocent people facing the prospect of violence on a horrific scale\xe2\x80\x94\nwhen we have a mandate to help\xe2\x80\x94in this case, a request from the\nIraqi government\xe2\x80\x94and when we have the unique capabilities to help\navert a massacre, then I believe the United States of America cannot\nturn a blind eye. We can act, carefully and responsibly, to prevent a\npotential act of genocide.\nPresident Obama August 7 Statement. The President declined to specify a\nparticular timetable for the airstrikes. See President Obama August 9\nStatement. But he also emphasized that the United States was \xe2\x80\x9cnot going\nto have . . . combat troops in Iraq again.\xe2\x80\x9d Id. 4\nConsistent with the War Powers Resolution, 50 U.S.C. \xc2\xa7 1543(a), President Obama provided a report to Congress less than forty-eight hours\nafter the operations began:\nAs I announced publicly on August 7, 2014, I have authorized the\nU.S. Armed Forces to conduct targeted airstrikes in Iraq. These military operations will be limited in their scope and duration as necessary to protect American personnel in Iraq by stopping the current\nadvance on Erbil by the terrorist group Islamic State of Iraq and the\nLevant and to help forces in Iraq as they fight to break the siege of\nMount Sinjar and protect the civilians trapped there.\nPursuant to this authorization, on August 8, 2014, U.S. military\nforces commenced targeted airstrike operations in Iraq.\n4 On August 13, a senior White House official stated that the United States would consider using U.S. ground troops to assist the Iraqi government in evacuating refugees from\nMount Sinjar but reiterated the President\xe2\x80\x99s commitment not to \xe2\x80\x9creintroduc[e] U.S. forces\ninto combat on the ground in Iraq.\xe2\x80\x9d Colin Campbell, White House: We May Use Combat\nTroops for Iraq Operation, Bus. Insider, Aug. 13, 2014, https://www.businessinsider.com/\nwhite-house-we-may-use-combat-troops-in-iraq-2014-8; see also id. (senior official\nexplaining that any deployment of ground troops to assist in evacuating refuges would be\n\xe2\x80\x9cdifferent than reintroducing U.S. forces in a combat role to take the fight to ISIL\xe2\x80\x9d).\nUltimately, the President determined that ground troops were not necessary because the\nhumanitarian airdrops and airstrikes had been successful. See President Obama August 14\nStatement.\n\n90\n\n\x0cTargeted Airstrikes Against the Islamic State of Iraq and the Levant\n\nIn addition, I have authorized U.S. Armed Forces to provide humanitarian assistance in Iraq in an operation that commenced on August 7, 2014. These operations will also be limited to supporting the\ncivilians trapped on Mount Sinjar.\nOffice of the Press Secretary, The White House, Letter from the President\xe2\x80\x94War Powers Resolution Regarding Iraq (Aug. 8, 2014) (\xe2\x80\x9cAugust 8\nReport to Congress\xe2\x80\x9d), https://obamawhitehouse.archives.gov/the-pressoffice/2014/08/08/letter-president-war-powers-resolution-regarding-iraq.\nThe report also explained that, in the President\xe2\x80\x99s judgment, the actions\nwere \xe2\x80\x9cin the national security and foreign policy interests of the United\nStates.\xe2\x80\x9d Id. As authority for the military operations, President Obama\ninvoked his \xe2\x80\x9cconstitutional authority to conduct U.S. foreign relations\xe2\x80\x9d\nand his authority \xe2\x80\x9cas Commander in Chief and Chief Executive.\xe2\x80\x9d Id.\nThe President and other administration officials emphasized on multiple occasions that both operations were undertaken at the specific request of the Iraqi government. See, e.g., President Obama August 7\nStatement; News Transcript, U.S. Dep\xe2\x80\x99t of Def., Remarks by Secretary\nHagel at a Troop Event, San Diego, California (Aug. 12, 2014), http://\narchive.defense.gov/Transcripts/Transcript.aspx?TranscriptID=5485. The\nPresident\xe2\x80\x99s report to Congress likewise indicated that these actions were\n\xe2\x80\x9cbeing undertaken in coordination with the Iraqi government.\xe2\x80\x9d August 8\nReport to Congress.\nAirstrikes Near Mosul Dam. On August 14, the President authorized\nfurther targeted airstrikes against ISIL positions around the Mosul Dam\nto assist the Iraqi forces in recapturing and establishing control of the\ndam. See Office of the Press Secretary, The White House, Letter from\nthe President\xe2\x80\x94War Powers Resolution Regarding Iraq (Aug. 17, 2014)\n(\xe2\x80\x9cAugust 17 Report to Congress\xe2\x80\x9d), https://obamawhitehouse.archives.\ngov/the-press-office/2014/08/17/letter-president-war-powers-resolutionregarding-iraq. In a report to Congress describing his authorization of\nthis third set of airstrikes, the President cited the dangers posed by ISIL\xe2\x80\x99s\ncontrol of the dam:\nOn August 14, 2014, I authorized the U.S. Armed Forces to conduct\ntargeted air strikes to support operations by Iraqi forces to recapture\nthe Mosul Dam. These military operations will be limited in their\nscope and duration as necessary to support the Iraqi forces in their\n91\n\n\x0c38 Op. O.L.C. 82 (2014)\n\nefforts to retake and establish control of this critical infrastructure\nsite, as part of their ongoing campaign against the terrorist group the\nIslamic State of Iraq and the Levant (ISIL). The failure of the Mosul\nDam could threaten the lives of large numbers of civilians, endanger\nU.S. personnel and facilities, including the U.S. Embassy in Baghdad, and prevent the Iraqi government from providing critical services to the Iraqi populace.\nId. Administration officials noted that the airstrikes against ISIL positions\nin and around the Mosul Dam, like the prior sets of strikes, were undertaken \xe2\x80\x9cat the request of the Iraqi government.\xe2\x80\x9d U.S. Dep\xe2\x80\x99t of Def., News\nRelease, No. NR-432-14, Statement from Pentagon Press Secretary Rear\nAdmiral John Kirby (Aug. 18, 2014), http://archive.defense.gov/Releases/\nRelease.aspx?ReleaseID=16891. The strikes began on August 15 and ultimately assisted Iraqi forces in regaining control of the dam. See id.\nAirstrikes Near Amirli. By late August, it had become clear that a humanitarian crisis was developing in Amirli, a town in northern Iraq\npopulated by Shiite Turkmen that had been besieged by ISIL militants for\nmany weeks. See, e.g., Ben Hubbard, Dozens Killed at Sunni Mosque in\nIraq After Attack on Shiite Leader, N.Y. Times Int\xe2\x80\x99l, Aug. 22, 2014, at\nA6. The siege had left the community without sufficient food, water, or\nmedical supplies, and Iraqi leaders and human rights officials were\nappealing to the international community for assistance. See id. Further,\nbecause ISIL viewed the Shiite residents of the town as \xe2\x80\x9cinfidels,\xe2\x80\x9d the\nmembers of the community faced possible mass executions if ISIL\ngained control of the town. See id.; see also State Department June 15\nPress Statement (noting ISIL\xe2\x80\x99s claim that it had massacred 1700 Iraqi\nShiite air force recruits). In light of these developments, the State Department indicated that the United States was \xe2\x80\x9cvery concerned about the\ndire conditions for the mainly Turkmen population in Amirli.\xe2\x80\x9d Office of\nPress Relations, U.S. Dep\xe2\x80\x99t of State, Daily Press Briefing (Aug. 28,\n2014) (\xe2\x80\x9cState Department August 28 Daily Press Briefing\xe2\x80\x9d), https://20092017.state.gov/r/pa/prs/dpb/2014/08/231125.htm. This concern was also\nreflected in earlier calls by U.N. officials for \xe2\x80\x9cimmediate action to prevent the possible massacre of [Amirli\xe2\x80\x99s] citizens\xe2\x80\x9d and to address the\n\xe2\x80\x9cdesperate\xe2\x80\x9d situation and \xe2\x80\x9cinhuman conditions\xe2\x80\x9d there. UN News, Iraq:\nUN Envoy Calls for Immediate Action to Avert Possible \xe2\x80\x9cMassacre\xe2\x80\x9d in\n92\n\n\x0cTargeted Airstrikes Against the Islamic State of Iraq and the Levant\n\nNorthern Town (Aug. 23, 2014), https://news.un.org/en/story/2014/08/\n475762-iraq-un-envoy-calls-immediate-action-avert-possible-massacrenorthern-town; see also Office of the High Commissioner, U.N. Human\nRights, Iraqi Civilians Suffering \xe2\x80\x9cHorrific\xe2\x80\x9d Widespread and Systematic\nPersecution\xe2\x80\x94Pillay (Aug. 25, 2014) (noting the \xe2\x80\x9cpossible imminent\nmassacre\xe2\x80\x9d of the 13,000 members of the Amirli Turkmen community and\ncalling upon the \xe2\x80\x9cGovernment of Iraq and the Kurdistan region of Iraq,\nand the international community\xe2\x80\x9d to \xe2\x80\x9ctake all necessary measures . . . to\nprotect members of ethnic and religious communities\xe2\x80\x9d), https://www.\nohchr.org/EN/NewsEvents/Pages/DisplayNews.aspx?NewsID=14961&\nLangID=E.\nOn August 28, in response to this unfolding humanitarian crisis, President Obama authorized airdrops of supplies to Amirli as well as \xe2\x80\x9ctargeted airstrikes in support of [the humanitarian] operation.\xe2\x80\x9d Office of\nthe Press Secretary, The White House, Letter from the President\xe2\x80\x94War\nPowers Resolution Regarding Iraq (Sept. 1, 2014) (\xe2\x80\x9cSeptember 1 Report\nto Congress\xe2\x80\x9d), https://obamawhitehouse.archives.gov/the-press-office/\n2014/09/01/letter-president-war-powers-resolution-regarding-iraq. U.S.\naircraft dropped 109 bundles of humanitarian aid by August 31, and\nadditional aid was delivered by coordinated British, French, and Australian airdrops. See News Release, U.S. Central Command, Release No.\n20140835, U.S. Military Conducts Airstrikes Against ISIL, Airdrops\nHumanitarian Aid Near Amirli (Aug. 30, 2014) (\xe2\x80\x9cCENTCOM August 30\nRelease\xe2\x80\x9d), http://www.centcom.mil/MEDIA/NEWS-ARTICLES/NewsArticle-View/Article/884834/us-military-conducts-airstrikes-against-isilairdrops-humanitarian-aid-near-ami. U.S. aircraft also conducted strikes\non ISIL positions in support of the humanitarian operation. Id.\nWithin forty-eight hours after the Amirli operation began, President\nObama reported the operation to Congress:\nOn August 28, 2014, I . . . authorized U.S. Armed Forces to conduct\ntargeted airstrikes in support of an operation to deliver humanitarian\nassistance to civilians in the town of Amirli, Iraq, which is surrounded and besieged by ISIL. Pursuant to this authorization, on August\n30, 2014, U.S. military forces commenced targeted airstrike operations in the vicinity of Amirli, Iraq. These additional operations will\nbe limited in their scope and duration as necessary to address this\n93\n\n\x0c38 Op. O.L.C. 82 (2014)\n\nemerging humanitarian crisis and protect the civilians trapped in\nAmirli.\nSeptember 1 Report to Congress. The President indicated that the Amirli\noperation, like the previous operations, had been \xe2\x80\x9cundertaken in coordination with and at request of the Iraqi government.\xe2\x80\x9d Id.; see also CENTCOM August 30 Release (noting the actions were taken \xe2\x80\x9c[a]t the request\nof the Government of Iraq\xe2\x80\x9d).\nAirstrikes Near Haditha Dam. Throughout August, ISF and allied tribal fighters maintained control of the Haditha Dam against advances by\nISIL militants. See Jihadists Rout Kurds, N.Y. Times, Aug. 8, 2014, at\nA1; Helene Cooper et al., U.S. Intervention in Iraq Extends to a Second\nDam, N.Y. Times, Sept. 8, 2014, at A8. On September 6, 2014, to support\nthese efforts, President Obama authorized the U.S. military to launch\nairstrikes against ISIL positions around the dam. See Office of the Press\nSecretary, The White House, Letter from the President\xe2\x80\x94War Powers\nResolution Regarding Iraq (Sept. 8, 2014) (\xe2\x80\x9cSeptember 8 Report to Congress\xe2\x80\x9d), https://obamawhitehouse.archives.gov/the-press-office/2014/09/\n08/letter-president-war-powers-resolution-regarding-iraq. These airstrikes\nwere conducted \xe2\x80\x9cin support of Iraqi Security Forces\xe2\x80\x99 efforts to retain\ncontrol\xe2\x80\x9d of the dam, because the \xe2\x80\x9cdestruction of the dam or release of\nwater would create a level of flooding that would potentially pose a catastrophic threat to thousands of Iraqis along the Euphrates valley from\nAnbar province into parts of Baghdad, including possible flooding in\nareas in and around the Baghdad International Airport, where hundreds of\nU.S. personnel reside.\xe2\x80\x9d Office of the Press Secretary, The White House,\nStatement by NSC Spokesperson Caitlin Hayden on Airstrikes Around the\nHaditha Dam (Sept. 7, 2014) (\xe2\x80\x9cNSC September 7 Statement\xe2\x80\x9d), https://\nobamawhitehouse.archives.gov/the-press-office/2014/09/07/statementnsc-spokesperson-caitlin-hayden-airstrikes-around-haditha-dam; see also\nNews Release, U.S. Dep\xe2\x80\x99t of Defense, Release No. NR-468-14, Statement\nfrom Pentagon Press Secretary Rear Admiral John Kirby on Haditha Dam\nAirstrikes (Sept. 7, 2014), http://archive.defense.gov/Releases/Release.\naspx?ReleaseID=16927 (noting that flooding that might have resulted\nfrom a catastrophic failure of the dam \xe2\x80\x9cwould have threatened U.S. personnel and facilities in and around Baghdad, as well as thousands of Iraqi\n94\n\n\x0cTargeted Airstrikes Against the Islamic State of Iraq and the Levant\n\ncitizens\xe2\x80\x9d). President Obama reported this operation to Congress within\nforty-eight hours:\nOn September 6, 2014, pursuant to my authorization, U.S. Armed\nForces commenced targeted airstrikes in the vicinity of the Haditha\nDam in support of Iraqi forces in their efforts to retain control of and\ndefend this critical infrastructure site from ISIL. These additional\nmilitary operations will be limited in their scope and duration as\nnecessary to address this threat and prevent endangerment of U.S.\npersonnel and facilities and large numbers of Iraqi civilians.\nSeptember 8 Report to Congress. President Obama again emphasized\nthat, as in prior operations, he had authorized the use of force \xe2\x80\x9cin coordination with and at the request of the Iraqi government.\xe2\x80\x9d Id.; see also U.S.\nDep\xe2\x80\x99t of Def., News Transcript, Joint Press Availability by Secretary\nHagel and Minister Alasania in Georgia (Sept. 7, 2014), http://archive.\ndefense.gov/Transcripts/Transcript.aspx?TranscriptID=5499 (noting that\nthe \xe2\x80\x9cIraqi security forces on the ground . . . conceived of the operation\xe2\x80\x9d\nand the \xe2\x80\x9cIraqi government asked [the United States] for [its] support in\nth[e] strikes\xe2\x80\x9d). 5\nII.\nIn our recent opinion concerning the President\xe2\x80\x99s authority to conduct\nmilitary operations in Libya, we explained in detail our framework for\nanalyzing the President\xe2\x80\x99s legal authority to use military force abroad\nwithout prior congressional authorization. See Authority to Use Military\nForce in Libya, 35 Op. O.L.C. 20, 27\xe2\x80\x9333 (2011) (\xe2\x80\x9cMilitary Force in\nLibya\xe2\x80\x9d). In light of that discussion, we need not provide a detailed explanation of our framework here. Instead, we will summarize briefly the\n\nAlthough the President had begun developing his new comprehensive strategy to\ncounter ISIL at the time that he authorized airstrikes around the Haditha Dam, see supra\nnote 1, it is our understanding that those airstrikes were not intended to implement the\nnew strategy, which had not yet been finalized or announced when the strikes were\ninitiated. Rather, as the President\xe2\x80\x99s Report to Congress explains, the Haditha airstrikes\nwere an independent operation \xe2\x80\x9climited in their scope and duration\xe2\x80\x9d as necessary to\nprotect the dam, U.S. personnel and facilities, and Iraqi civilians. September 8 Report to\nCongress.\n5\n\n95\n\n\x0c38 Op. O.L.C. 82 (2014)\n\nrelevant legal principles before applying them to the airstrike operations\ndescribed above.\nAs our Libya opinion explains, Attorneys General and this Office have\nconsistently concluded that \xe2\x80\x9c\xe2\x80\x98the President has the power to commit\nUnited States troops abroad,\xe2\x80\x99 as well as to \xe2\x80\x98take military action,\xe2\x80\x99 \xe2\x80\x98for the\npurpose of protecting important national interests,\xe2\x80\x99 even without specific\nprior authorization from Congress.\xe2\x80\x9d Id. at 27\xe2\x80\x9328 (quoting Authority to\nUse United States Military Forces in Somalia, 16 Op. O.L.C. 6, 9 (1992)\n(\xe2\x80\x9cMilitary Forces in Somalia\xe2\x80\x9d)). This power is rooted in the President\xe2\x80\x99s\nconstitutional authority as Chief Executive and Commander in Chief of\nthe armed forces. U.S. Const. art. II, \xc2\xa7 1, cl. 1; id. \xc2\xa7 2, cl. 1. The assignment of the \xe2\x80\x9cexecutive Power\xe2\x80\x9d to the President has, over time, been\nunderstood to give him the \xe2\x80\x9c\xe2\x80\x98vast share of responsibility for the conduct\nof our foreign relations,\xe2\x80\x99\xe2\x80\x9d Am. Ins. Ass\xe2\x80\x99n v. Garamendi, 539 U.S. 396, 414\n(2003) (quoting Youngstown Sheet & Tube Co. v. Sawyer, 343 U.S. 579,\n610 \xe2\x80\x9311 (1952) (Frankfurter, J., concurring)), as well as \xe2\x80\x9cindependent\nauthority \xe2\x80\x98in the areas of foreign policy and national security,\xe2\x80\x99\xe2\x80\x9d id. at 429\n(quoting Haig v. Agee, 453 U.S. 280, 291 (1981)). And the President\xe2\x80\x99s\nauthority as Commander in Chief gives him the authority to superintend\nand direct the movements of the military forces placed at his command.\nSee Loving v. United States, 517 U.S. 748, 772 (1996); Fleming v. Page,\n50 U.S. (9 How.) 603, 615 (1850). The President also holds an \xe2\x80\x9cimplicit\nadvantage . . . over the legislature under our constitutional scheme in situations calling for immediate action,\xe2\x80\x9d because of his ability to act and\nrespond to developing situations with greater facility and speed. Presidential Power to Use the Armed Forces Abroad Without Statutory Authorization, 4A Op. O.L.C. 185, 187 (1980) (\xe2\x80\x9cPresidential Power\xe2\x80\x9d); see also\nPresidential Authority to Permit Incursion Into Communist Sanctuaries in\nthe Cambodia-Vietnam Border Area, 1 Op. O.L.C. Supp. 313, 314 (1970)\n(noting that the Framers \xe2\x80\x9crecognized the need for quick executive response to rapidly developing international situations\xe2\x80\x9d).\nPresidents have exercised these authorities numerous times throughout\nthe Nation\xe2\x80\x99s history to deploy the armed forces abroad without either a\ndeclaration of war or other congressional authorization, beginning in the\nearliest days of the Republic. See Military Forces in Somalia, 16 Op.\nO.L.C. at 9 (citing an example from 1801); Presidential Power, 4A Op.\nO.L.C. at 187 (\xe2\x80\x9cOur history is replete with instances of presidential uses\n96\n\n\x0cTargeted Airstrikes Against the Islamic State of Iraq and the Levant\n\nof military force abroad in the absence of prior congressional approval.\xe2\x80\x9d).\nSee generally Barbara Salazar Torreon, Cong. Research Serv., R42738,\nInstances of Use of United States Armed Forces Abroad, 1798\xe2\x80\x932013, at\n2\xe2\x80\x9333 (Aug. 30, 2013) (\xe2\x80\x9cInstances of Force Abroad \xe2\x80\x9d) (citing numerous\nexamples). In the foreign affairs and national security context, where\njudicial review is rare, see Agee, 453 U.S. at 292, such a \xe2\x80\x9cpattern of\nexecutive conduct, made under claim of right, extended over many decades[,] and engaged in by Presidents of both parties, evidences the existence of broad constitutional power.\xe2\x80\x9d Military Force in Libya, 35 Op.\nO.L.C. at 29\xe2\x80\x9330 (internal quotation marks omitted); see also Proposed\nDeployment of United States Armed Forces into Bosnia, 19 Op. O.L.C.\n327, 330\xe2\x80\x9331 (1995) (\xe2\x80\x9cProposed Bosnia Deployment \xe2\x80\x9d) (noting that the\n\xe2\x80\x9cscope and limits\xe2\x80\x9d of the President\xe2\x80\x99s and Congress\xe2\x80\x99s respective powers\nhave been \xe2\x80\x9cclarified by 200 years of practice\xe2\x80\x9d).\nTo be sure, the Constitution also gives Congress the power to \xe2\x80\x9cdeclare\nWar,\xe2\x80\x9d to provide for the common defense, and to raise, support, maintain,\nand make rules for the armed forces. U.S. Const. art. I, \xc2\xa7 8, cls. 1, 11\xe2\x80\x9314.\nThese congressional powers may limit the President\xe2\x80\x99s authority to initiate\nwithout prior congressional authorization a \xe2\x80\x9cprolonged and substantial\xe2\x80\x9d\n\xe2\x80\x9cplanned military engagement that constitutes a \xe2\x80\x98war\xe2\x80\x99 within the meaning\nof the Declaration of War Clause.\xe2\x80\x9d Military Force in Libya, 35 Op.\nO.L.C. at 31. They may also permit Congress in certain respects to restrict\nhow the President exercises his military authorities. See id. at 28. But \xe2\x80\x9cthe\nhistorical practice of presidential military action without congressional\napproval precludes any suggestion that Congress\xe2\x80\x99s authority to declare\nwar covers every military engagement, however limited, that the President\ninitiates.\xe2\x80\x9d Id. at 31. Indeed, \xe2\x80\x9cCongress itself has implicitly recognized\xe2\x80\x9d\nthe President\xe2\x80\x99s unilateral authority to initiate military engagements in the\nWar Powers Resolution, which, by imposing reporting and other requirements on the President\xe2\x80\x99s introduction of armed forces into hostilities or\nimminent hostilities absent a congressional declaration of war, \xe2\x80\x9c\xe2\x80\x98recognizes and presupposes the existence of unilateral presidential authority to\ndeploy armed forces\xe2\x80\x99\xe2\x80\x9d into such situations. Id. at 30 (quoting Deployment\nof United States Armed Forces into Haiti, 18 Op. O.L.C. 173, 175 (1994)\n(\xe2\x80\x9c1994 Haiti Deployment \xe2\x80\x9d)).\nSynthesizing these precedents in our Libya opinion, we explained that,\nin any particular instance, the President\xe2\x80\x99s authority to order military\n97\n\n\x0c38 Op. O.L.C. 82 (2014)\n\naction abroad without prior congressional approval turns on two considerations: first, whether the contemplated action would serve \xe2\x80\x9csufficiently\nimportant national interests\xe2\x80\x9d to \xe2\x80\x9cpermit the President\xe2\x80\x99s action as Commander in Chief and Chief Executive\xe2\x80\x9d; and second, whether the contemplated action would be sufficiently limited in \xe2\x80\x9cnature, scope, and duration\xe2\x80\x9d so as not to constitute a \xe2\x80\x9cwar\xe2\x80\x9d requiring prior congressional approval under the Declaration of War Clause. Id. at 33. We now turn to an\nanalysis of the airstrike operations detailed above under this two-part\nframework.\nA.\nWe consider first whether the operations served \xe2\x80\x9csufficiently important\nnational interests\xe2\x80\x9d to fall within the President\xe2\x80\x99s constitutional authority as\nCommander in Chief and Chief Executive. Military Force in Libya, 35\nOp. O.L.C. at 33. In authorizing the targeted airstrikes against ISIL,\nPresident Obama identified at least three relevant national interests:\nprotecting American lives and property; assisting an ally or strategic\npartner at its request; and protecting endangered populations against\nhumanitarian atrocities, including possible genocide. In our view, a\ncombination of these interests supported the President\xe2\x80\x99s constitutional\nauthority as Commander in Chief to order each of the airstrike operations\ndescribed above without express congressional authorization.\n1.\nThe first national interest identified by President Obama\xe2\x80\x94the protection of American citizens and property\xe2\x80\x94has long been recognized as a\nbasis on which Presidents may authorize military action abroad without\nprior congressional approval. See Presidential Power, 4A Op. O.L.C. at\n121 (\xe2\x80\x9cIt is well established that the President has the constitutional power\nas Chief Executive and Commander-in-Chief to protect the lives and\nproperty of Americans abroad.\xe2\x80\x9d); Military Forces in Somalia, 16 Op.\nO.L.C. at 9 (\xe2\x80\x9cAt the core of \xe2\x80\x9d the President\xe2\x80\x99s power to use military force\nwithout prior congressional authorization \xe2\x80\x9cis the President\xe2\x80\x99s authority to\ntake military action to protect American citizens, property, and interests\nfrom foreign threats.\xe2\x80\x9d); see also United States v. Verdugo-Urquidez, 494\nU.S. 259, 273 (1990) (noting that \xe2\x80\x9c[t]he United States frequently employs\n98\n\n\x0cTargeted Airstrikes Against the Islamic State of Iraq and the Levant\n\nArmed Forces outside this country . . . for the protection of American\ncitizens\xe2\x80\x9d); In re Neagle, 135 U.S. 1, 63\xe2\x80\x9364 (1890) (recognizing that the\nobligation to protect American citizens abroad is among the President\xe2\x80\x99s\n\xe2\x80\x9crights, duties, and obligations growing out of the Constitution itself \xe2\x80\x9d);\nDurand v. Hollins, 8 F. Cas. 111, 112 (C.C.S.D.N.Y. 1860) (No. 4186)\n(stating that \xe2\x80\x9cthe interposition of the president abroad, for the protection\nof the citizen, must necessarily rest in his discretion\xe2\x80\x9d). Presidents have\nrelied on this interest numerous times to support both defensive and\noffensive military action abroad. See, e.g., J. Reuben Clark, U.S. Solicitor,\nDep\xe2\x80\x99t of State, Right to Protect Citizens in Foreign Countries by Landing\nForces 34\xe2\x80\x9338 (3d rev. ed. 1933) (\xe2\x80\x9cRight to Protect \xe2\x80\x9d) (collecting examples\nprior to 1910); Authority of the President to Repel the Attack in Korea, 23\nDep\xe2\x80\x99t of State Bull. 173, 177\xe2\x80\x9378, reprinted in H.R. Rep. No. 81-2495, at\n61, 67\xe2\x80\x9368 (1950) (collecting examples between 1812 and 1932) (\xe2\x80\x9cKorea\nMemorandum\xe2\x80\x9d); Instances of Force Abroad at 2\xe2\x80\x9333 (citing additional\nexamples). President McKinley, for instance, dispatched 5,000 troops to\nChina in significant part to protect American lives and property during the\nBoxer Rebellion. See William McKinley, Annual Message of the President to Congress (Dec. 3, 1900), Papers Relating to the Foreign Relations\nof the United States, 1900, at XI\xe2\x80\x93XIV (1902) (describing the operation in\ndetail); see also Deployment of United States Armed Forces to Haiti, 28\nOp. O.L.C. 30, 32 (2004) (\xe2\x80\x9c2004 Haiti Deployment \xe2\x80\x9d). President Taft sent\nmore than 2,000 troops to Nicaragua in 1912 in part to protect Americans\nduring an ongoing revolution in that country. Right to Protect at 119\xe2\x80\x9322;\nsee also W.H. Taft, Annual Message of the President to Congress (Dec. 3,\n1912), Papers Relating to the Foreign Relations of the United States,\n1912, at XII\xe2\x80\x93XIII (1919). And President Johnson ordered military intervention in the Dominican Republic in 1965 in large part to protect Americans living there. See 2004 Haiti Deployment, 28 Op. O.L.C. at 32. More\nrecently, in 2004, President George W. Bush deployed troops to Haiti in\npart to protect the thousands of Americans living there who \xe2\x80\x9cwould [have\nbeen] in danger if the country [had] descend[ed] into lawlessness.\xe2\x80\x9d Id.\nIn our view, it was reasonable for the President to rely on a national\ninterest in protecting American personnel and property in authorizing the\nairstrikes around Erbil, the Mosul Dam, and the Haditha Dam. As noted\nearlier, numerous American military advisers, diplomats, and other civilians are based in Erbil. Given ISIL\xe2\x80\x99s brutal treatment of the populations it\n99\n\n\x0c38 Op. O.L.C. 82 (2014)\n\nencounters and those who oppose its aims, see supra Part I, the lives of\nthese Americans would have been placed in jeopardy if ISIL had taken\ncontrol of Erbil. The airstrikes against ISIL forces outside the city were\ntherefore justified in order to protect these American lives. Similarly,\nAmerican lives and property in Baghdad would have been placed in\njeopardy if ISIL had destroyed the Mosul Dam\xe2\x80\x94whether through purposeful action or an inability to perform the \xe2\x80\x9cextraordinary engineering\nmeasures\xe2\x80\x9d necessary to maintain it, Geologic Setting of Mosul Dam at 2\xe2\x80\x94\nor if ISIL had taken control of and destroyed or released floodwaters from\nthe Haditha Dam, see NSC September 7 Statement. More than 5,000\ncontractors, including 2,000 U.S. citizens, were working at the U.S.\nEmbassy in Baghdad as of June. See Dan Lamothe, Diplomats, Pilots, and\nHired Guns: Here Are the Americans Left in Iraq, Wash. Post, June 12,\n2014, https://www.washingtonpost.com/news/checkpoint/wp/2014/06/12/\ndiplomats-pilots-and-hired-guns-here-are-the-americans-left-in-iraq.\nThe destruction of the Mosul Dam could have resulted in flooding in\nBaghdad, see Mosul Dam Letter, which the President determined could\nhave \xe2\x80\x9cendanger[ed] U.S. personnel and facilities, including the U.S.\nEmbassy in Baghdad, and prevent[ed] the Iraqi government from providing critical services\xe2\x80\x9d to the populace. August 17 Report to Congress. The\ndestruction of the Haditha Dam could similarly have caused flooding in\nthe southern areas of Baghdad, including areas where U.S. personnel are\nlocated, which the President determined could have \xe2\x80\x9cendanger[ed] U.S.\npersonnel and facilities.\xe2\x80\x9d September 8 Report to Congress; see also NSC\nSeptember 7 Statement. In light of these risks, it was also reasonable for\nthe President to rely on the national interest in protecting U.S. personnel\nand property in authorizing military action to help Iraqi forces retake the\nMosul Dam and retain control of the Haditha Dam.\n2.\nIn authorizing the airstrike operations at issue in this opinion, President\nObama also invoked a national interest in assisting Iraq, a strategic partner, in its campaign against ISIL. See August 8 Report to Congress (indicating the airstrikes near Erbil and Mount Sinjar would \xe2\x80\x9chelp forces in\nIraq\xe2\x80\x9d and were \xe2\x80\x9cundertaken in coordination with the Iraqi government\xe2\x80\x9d);\nAugust 17 Report to Congress (indicating the airstrikes around the Mosul\n100\n\n\x0cTargeted Airstrikes Against the Islamic State of Iraq and the Levant\n\nDam were undertaken \xe2\x80\x9cto support the Iraqi forces in their efforts\xe2\x80\x9d to\nrecapture the dam and in \xe2\x80\x9ctheir ongoing campaign against [ISIL]\xe2\x80\x9d); September 1 Report to Congress (noting the operation had been undertaken\n\xe2\x80\x9cin coordination with and at the request of the Iraqi government\xe2\x80\x9d); September 8 Report to Congress (indicating the airstrikes around Haditha\nDam were undertaken \xe2\x80\x9cin support of Iraqi forces in their efforts to retain\ncontrol of and defend this critical infrastructure site from ISIL\xe2\x80\x9d). We\nbelieve that it was reasonable for the President to rely on this interest, in\ncombination with a national interest in protecting American citizens and\nproperty or averting a humanitarian catastrophe, in ordering the use of\nmilitary force abroad.\nOur Office has previously recognized that, in authorizing military action abroad, the President may rely on a national interest in assisting an\nally or strategic partner at its request. In our 1980 opinion on possible\nuses of force related to the Iranian hostage crisis, for example, we identified \xe2\x80\x9cdefending our allies\xe2\x80\x9d as a purpose for which the President may\nconstitutionally use force without prior congressional approval, and\npointed to the deployment of troops to Korea as \xe2\x80\x9cprecedent . . . for the\ncommitment of United States armed forces, without prior congressional\napproval or declaration of war, to aid an ally in repelling an armed\ninvasion.\xe2\x80\x9d Presidential Power, 4A Op. O.L.C. at 186 n.2, 187\xe2\x80\x9388. 6\nSimilarly, in our 1994 opinion concluding that the President had constitutional authority to send 20,000 troops to Haiti to forcibly remove its\nmilitary dictators from power, we relied in significant part on the fact that\nthe planned deployment was to take place at the invitation of Haiti\xe2\x80\x99s\nlegitimate government, citing in support several prior examples of Presidents deploying the military abroad at the request of foreign countries.\n6 The fact that this national interest supported the Korea operation does not mean that\nthe Korea deployment was sufficiently limited in nature, scope, and duration to be within\nthe President\xe2\x80\x99s constitutional authority to act without congressional authorization. See\n1994 Haiti Deployment, 18 Op. O.L.C. at 178\xe2\x80\x9379. We take no position on the latter\nquestion in this opinion. See The President and the War Power: South Vietnam and the\nCambodian Sanctuaries, 1 Op. O.L.C. Supp. 321, 329 (1970) (noting that President\nTruman\xe2\x80\x99s action in Korea had ignited a \xe2\x80\x9cGreat Debate\xe2\x80\x9d in Congress over the President\xe2\x80\x99s\nwar power); Proposed Bosnia Deployment, 19 Op. O.L.C. at 331\xe2\x80\x9332 n.5 (noting that\n\xe2\x80\x9c[t]he boldest claim of Executive authority to wage war without congressional authorization was made at the time of the Korean War,\xe2\x80\x9d and that \xe2\x80\x9c[s]uch sweeping claims of\ninherent Executive authority have been sharply criticized\xe2\x80\x9d).\n\n101\n\n\x0c38 Op. O.L.C. 82 (2014)\n\n1994 Haiti Deployment, 18 Op. O.L.C. at 174 n.1, 178\xe2\x80\x9379 & n.10 7; see\nalso Leonard C. Meeker, Legal Adviser, Dep\xe2\x80\x99t of State, The Legality of\nThe discussion of U.S. military action taken at the request of foreign governments in\nour 1994 Haiti opinion appeared in the context of a discussion of the Declaration of War\nClause, rather than a discussion of national interests supporting an exercise of the Commander in Chief power. But that is because the entire constitutional discussion in that\nopinion was framed as a discussion of the Declaration of War Clause. This feature of the\nopinion is not unusual: the two-part inquiry we developed in our Libya opinion is a recent\nrefinement in this Office\xe2\x80\x99s jurisprudence, and our earlier opinions frequently analyzed the\nquestion of the President\xe2\x80\x99s constitutional authority to deploy the military abroad without\nprior congressional authorization under the rubric of a single inquiry, asking either\nwhether a contemplated military action fell within the President\xe2\x80\x99s constitutional power as\nCommander in Chief and Chief Executive to act in the national interest, see, e.g., 2004\nHaiti Deployment, 28 Op. O.L.C. at 31\xe2\x80\x9333; Military Forces in Somalia, 16 Op. O.L.C. at\n9\xe2\x80\x9312; Presidential Power, 4A Op. O.L.C. at 186\xe2\x80\x9388, or whether a proposed use of force\nwould constitute a \xe2\x80\x9cwar\xe2\x80\x9d within the meaning of the Constitution, see, e.g., Proposed\nBosnia Deployment, 19 Op. O.L.C. at 330\xe2\x80\x9334; 1994 Haiti Deployment, 18 Op. O.L.C. at\n177\xe2\x80\x9379. The analysis in these earlier opinions, however, frequently incorporated in\nsubstance both components of the two-part framework set forth above.\nThus, even though we considered assistance to an ally or partner in our 1994 Haiti\nopinion in the context of a discussion of the Declaration of War Clause, our opinion\nappeared to invoke that interest at least in part as a justification for the use of force\nabroad, not simply as an explanation for why the conflict was likely to be limited in\nnature, scope, and duration. In introducing historical examples of such assistance, for\nexample, we observed that \xe2\x80\x9cthe President, as Chief Executive and Commander in Chief\n. . . may, absent specific legislative restriction, deploy United States armed forces abroad\nor to any particular region,\xe2\x80\x9d and then noted that \xe2\x80\x9cPresidents have often utilized this\nauthority, in the absence of specific legislative authorization, to deploy United States\nmilitary personnel into foreign countries at the invitation of the legitimate governments of\nthose countries.\xe2\x80\x9d 1994 Haiti Deployment, 18 Op. O.L.C. at 178 (internal quotation marks\nomitted). This formulation suggests that we recognized that prior Presidents had considered a foreign government\xe2\x80\x99s request for assistance to be an overall justification for the\ndeployment of troops abroad under their Chief Executive and Commander in Chief\nauthority, not simply an indicator of a conflict\xe2\x80\x99s likely scope. The examples of prior\npresidential action we cited in our opinion are consistent with this characterization. See\ninfra pp. 103 \xe2\x80\x93109 (discussing examples of Nicaragua, Greenland, Iceland, and the\nPhilippines also cited in 1994 Haiti opinion). Further\xe2\x80\x94and significantly\xe2\x80\x94our 1994 Haiti\nopinion also recognized that the mere fact that the United States \xe2\x80\x9cdeploys its troops into a\ncountry at the invitation of that country\xe2\x80\x99s legitimate government\xe2\x80\x9d does not mean that the\nengagement is not a \xe2\x80\x9cwar,\xe2\x80\x9d and conducted a separate analysis of the proposed Haitian\ndeployment\xe2\x80\x99s \xe2\x80\x9cnature, scope, and duration\xe2\x80\x9d to establish that it did not \xe2\x80\x9crise to the level of\n\xe2\x80\x98war.\xe2\x80\x99\xe2\x80\x9d 1994 Haiti Deployment, 18 Op. O.L.C. at 178\xe2\x80\x9379. These features of our 1994\nopinion suggest that its discussion of assistance to an ally or partner fits most naturally\ninto the \xe2\x80\x9cnational interest\xe2\x80\x9d element of our current two-part test.\n7\n\n102\n\n\x0cTargeted Airstrikes Against the Islamic State of Iraq and the Levant\n\nUnited States Participation in the Defense of Viet-Nam, 54 Dep\xe2\x80\x99t of State\nBull. 474, 489 (1966) (\xe2\x80\x9cParticipation in Viet-Nam\xe2\x80\x9d) (concluding that the\nPresident had constitutional \xe2\x80\x9cauthority to commit United States forces in\nthe collective defense of South Viet-Nam\xe2\x80\x9d on the request of that country\nand that \xe2\x80\x9c[t]his authority stems from the constitutional powers of the\nPresident\xe2\x80\x9d).\nHistorical practice is consistent with this position. Presidents have taken military action abroad or deployed U.S. military personnel into foreign countries without prior congressional approval on numerous occasions for the purpose of assisting an ally or partner at its request. In\nFebruary 1874, for example, rioting began in still-independent Hawaii\nafter the election of a new king. Right to Protect at 67. \xe2\x80\x9c[A]t the earnest\nsolicitation of [Hawaii\xe2\x80\x99s] government,\xe2\x80\x9d U.S. troops landed amid active\nrioting in Honolulu \xe2\x80\x9cto aid in restoring order.\xe2\x80\x9d Id. (quoting Report of the\nSecretary of the Navy, H.R. Exec. Doc. No. 43-1, pt. 3, at 8 (1874)); see\nalso Instances of Force Abroad at 6. In 1912, an attempted coup resulted\nin \xe2\x80\x9copen rebellion\xe2\x80\x9d against the government in Nicaragua. Papers Relating to the Foreign Relations of the United States, 1912, at 1032. In response, the Government of Nicaragua requested that the United States\n\xe2\x80\x9cguarantee with its forces security for the property of American citizens\xe2\x80\x9d\nand provide \xe2\x80\x9cprotection to all inhabitants of the Republic.\xe2\x80\x9d Id.; see also\nRight to Protect at 119\xe2\x80\x9320. Conveying this request to President Taft, the\nSecretary of State asked for the deployment of troops to Nicaragua \xe2\x80\x9cin\nview of the specific request of the Nicaraguan Government and of the\nseemingly possible danger of resultant anarchy.\xe2\x80\x9d Papers Relating to the\nForeign Relations of the United States, 1912, at 1032\xe2\x80\x9333. President Taft\ngranted the request. See id. at 1033. And in 1919, at the request of Italian\n\nWe do not mean to imply that if the government of a particular territory requests that\nthe United States use armed force in that territory, such a request cannot also be relevant\nin some circumstances to whether an action constitutes a \xe2\x80\x9cwar.\xe2\x80\x9d In our opinion regarding\na proposed deployment to Bosnia, for instance, we explained that the \xe2\x80\x9cconsensual nature\xe2\x80\x9d\nof the operation\xe2\x80\x94the fact that the parties who controlled the territory at issue had requested intervention\xe2\x80\x94tended to suggest that \xe2\x80\x9clittle or no resistance to the deployment\nw[ould] occur,\xe2\x80\x9d and served to distinguish the deployment of force from traditional wars\naimed at conquest or occupation of territory, both considerations that inform an analysis\nof the anticipated \xe2\x80\x9cnature, scope, and duration\xe2\x80\x9d of a conflict. Proposed Bosnia Deployment, 19 Op. O.L.C. at 332.\n\n103\n\n\x0c38 Op. O.L.C. 82 (2014)\n\nauthorities and without the prior knowledge or consent of Congress, U.S.\ntroops landed at Trau, Dalmatia\xe2\x80\x94territory that was the subject of a postWorld War I dispute between Italian and Serbian forces\xe2\x80\x94in order to\nprevent an imminent conflict. See Instances of Force Abroad at 9; Clarence Arthur Berdahl, War Powers of the Executive in the United States\n56 (1921). In response to a Senate resolution seeking information about\nthe incident, the Secretary of the Navy emphasized the \xe2\x80\x9cfact that Italian\nauthorit[ies] [had] requested [the] action\xe2\x80\x9d and that, had the United States\nnot acted, \xe2\x80\x9ca state of actual war\xe2\x80\x9d might have resulted. Landing Marines\nat Trau, Dalmatia, S. Doc. No. 66-117, at 2 (1919). 8\nSimilarly, before the United States joined the Second World War\xe2\x80\x94but\nafter the war had begun in Europe and it was feared that Germany might\nattack the Western Hemisphere\xe2\x80\x94President Franklin D. Roosevelt unilaterally authorized military action \xe2\x80\x9cdesigned to aid the allied forces\xe2\x80\x9d at the\nrequest of foreign officials. The President and the War Power: South\nVietnam and the Cambodian Sanctuaries, 1 Op. O.L.C. Supp. 321, 330\n(1970). Pursuant to an agreement made with a Danish minister, President\nRoosevelt ordered the U.S. military to occupy Greenland after Denmark\nfell to Germany in 1940. Id.; see also 1994 Haiti Deployment, 18 Op.\nO.L.C. at 178. And in 1941, he authorized U.S. troops to occupy Iceland\n\xe2\x80\x9cin defense of that country,\xe2\x80\x9d pursuant to an agreement he concluded with\nIceland\xe2\x80\x99s Prime Minister. Korea Memorandum, 23 Dep\xe2\x80\x99t of State Bull. at\n175, reprinted in H.R. Rep. No. 81-2495, at 65; see also 1994 Haiti\nDeployment, 18 Op. O.L.C. at 178. Although these actions plainly furthered the national security interest in preventing Germany from gaining a\nfoothold in the Western Hemisphere and attacking transatlantic shipping\nlanes, President Roosevelt indicated that the actions were also undertaken\nto assist friendly nations in defending their territory against Germany\xe2\x80\x99s\naggression. See Samuel I. Rosenman, The Public Papers and Addresses of\nIn congressional debates about the Trau incident, one Senator argued that the deployment of U.S. forces had been authorized by the \xe2\x80\x9cpractically unlimited resources and\nunlimited power\xe2\x80\x9d Congress had given the President to fight World War I. 58 Cong. Rec.\n6124\xe2\x80\x9325 (1919). But as other Senators pointed out, at the time the troops were sent to\nDalmatia, the United States had already signed an armistice, and in any event had never\nbeen at war with Italy or Serbia. See id. at 6123\xe2\x80\x9329; see also Landing at Trau Hotly\nCondemned in Senate Debate, N.Y. Times, Sept. 30, 1919 (describing the competing\nviews).\n8\n\n104\n\n\x0cTargeted Airstrikes Against the Islamic State of Iraq and the Levant\n\nFranklin D. Roosevelt 1941, at 262 (\xe2\x80\x9c[T]he Government of the United\nStates, while undertaking this defensive measure for the preservation of\nthe independence and security of the democracies of the New World,\n[will] at the same time be afforded the privilege of cooperating in this\nmanner with your Government in the defense of this historic democracy\nof Iceland.\xe2\x80\x9d (quoting message sent by President Roosevelt to the Prime\nMinister of Iceland)); id. at 96\xe2\x80\x9397 (quoting President Roosevelt\xe2\x80\x99s announcement that the establishment of U.S. bases in Greenland was \xe2\x80\x9cnew\nproof of our continuing friendliness to Denmark\xe2\x80\x9d).\nSeveral years later, in July of 1958, President Eisenhower sent a \xe2\x80\x9ccontingent of United States Marines\xe2\x80\x9d to Lebanon in response to an \xe2\x80\x9curgent\nrequest\xe2\x80\x9d from its president for assistance in the face of a \xe2\x80\x9cviolent insurrection\xe2\x80\x9d whose \xe2\x80\x9cavowed purpose\xe2\x80\x9d was to \xe2\x80\x9coverthrow the legally constituted government of Lebanon.\xe2\x80\x9d Special Message to the Congress on the\nSending of United States Forces to Lebanon (July 15, 1958), Pub. Papers\nof Pres. Dwight D. Eisenhower 550, 550\xe2\x80\x9351 (1958). President Eisenhower explained to Congress that \xe2\x80\x9cUnited States forces are being sent to\nLebanon to protect American lives and by their presence to assist the\nGovernment of Lebanon in the preservation of Lebanon\xe2\x80\x99s territorial\nintegrity and independence.\xe2\x80\x9d Id.; see also Statement by the President on\nthe Lebanese Government\xe2\x80\x99s Appeal for U.S. Forces (July 15, 1958),\nPub. Papers of Pres. Dwight D. Eisenhower 549, 549\xe2\x80\x9350 (1958). \xe2\x80\x9cAs we\nact at the request of a friendly government to help it preserve its independence and to preserve law and order which will protect American\nlives,\xe2\x80\x9d the President added, \xe2\x80\x9cwe are acting to reaffirm and strengthen\nprinciples upon which the safety and security of the United States depend.\xe2\x80\x9d Special Message to Congress on Lebanon, Pub. Papers of Pres.\nDwight D. Eisenhower at 552 (1958). Vice President Nixon made clear\nthat the \xe2\x80\x9cPresident had the constitutional power to do what he did\xe2\x80\x9d in\npart because of the U.S. interest in \xe2\x80\x9cstrengthen[ing] th[e] [Lebanese]\ngovernment in its efforts to resist forces in its country which were\nstimulated and materially assisted by forces outside the country.\xe2\x80\x9d 104\nCong. Rec. 14,548 (1958). The Vice President explained that the \xe2\x80\x9cfailure to come to the aid of a government that had been friendly to the\nUnited States\xe2\x80\x9d and had requested America\xe2\x80\x99s help \xe2\x80\x9cwould have struck\nfear and consternation and probably panic into the hearts of the friends\n105\n\n\x0c38 Op. O.L.C. 82 (2014)\n\nof the United States not only in that area, but all the way from Morocco\non the Atlantic clear over to the Pacific area.\xe2\x80\x9d Id. at 14,550. 9\nIn 1982, President Reagan again sent U.S. troops to Lebanon \xe2\x80\x9c[i]n response to the formal request of the Government of Lebanon,\xe2\x80\x9d this time to\nhelp ensure the departure of Palestine Liberation Organization leadership,\noffices, and combatants from Beirut and the restoration of Lebanese\ngovernment authority in the area. Letter to the Speaker of the House and\nthe President Pro Tempore of the Senate on the Deployment of United\nStates Forces in Beirut, Lebanon (Aug. 24, 1982), 2 Pub. Papers of Pres.\nRonald Reagan 1078, 1078 (1982). See generally The Situation in the\nMiddle East: Hearing Before the S. Comm. on Foreign Relations, 97th\nCong. 1\xe2\x80\x9314 (1982). In a notification to Congress \xe2\x80\x9cconsistent with the War\nPowers Resolution,\xe2\x80\x9d President Reagan stated that U.S. forces had been\ndeployed, \xe2\x80\x9cpursuant to the President\xe2\x80\x99s constitutional authority with respect to the conduct of foreign relations and as Commander-in-Chief of\nthe United States Armed Forces,\xe2\x80\x9d to \xe2\x80\x9cassist the Government of Lebanon\nin carrying out its responsibilities concerning the withdrawal [from Beirut] of . . . personnel [associated with the Palestine Liberation Organization] under safe and orderly conditions,\xe2\x80\x9d as agreed to by the Government\nof Lebanon, the Government of Israel, and the Palestine Liberation Or9 In 1957, Congress had passed a Joint Resolution to Promote Peace and Stability in\nthe Middle East, which gave the President the authority to \xe2\x80\x9cuse armed forces to assist\xe2\x80\x9d\nnations or groups of nations in the Middle East if they \xe2\x80\x9crequest[ed] assistance against\narmed aggression from any country controlled by international communism.\xe2\x80\x9d Pub. L. No.\n85-7, \xc2\xa7 2, 71 Stat. 5, 5 (1957). After President Eisenhower deployed troops to Lebanon,\nthere was some discussion in Congress about whether the deployment fit within the terms\nof this resolution, with several Senators expressing the position that it did not. See Arthur\nKrock, Law and Intervention: An Analysis of Eisenhower Doctrine\xe2\x80\x99s Application to U.S.\nLanding in Lebanon, N.Y. Times, July 16, 1958, at 8; see also Jane E. Stromseth, Understanding Constitutional War Powers Today: Why Methodology Matters, 106 Yale L.J.\n845, 870 n.132 (1996) (noting the debate on the question). In any event, Vice President\nNixon subsequently made clear that the President had acted solely in reliance on his\nconstitutional authority, see 104 Cong. Rec. 14,548 (1958), and later Executive Branch\nopinions have described President Eisenhower\xe2\x80\x99s deployment of troops to Lebanon as\nhaving been undertaken without statutory authorization, see, e.g., Participation in VietNam, 54 Dep\xe2\x80\x99t of State Bull. at 484\xe2\x80\x9385; Memorandum for President Lyndon Johnson\nfrom Secretary of State Dean Rusk, Re: Legal Basis for Sending American Forces to VietNam (June 29, 1964), reprinted in Stephen M. Griffin, A Bibliography of Executive\nBranch War Powers Opinions Since 1950, 87 Tul. L. Rev. 649, 658\xe2\x80\x9361 (2013).\n\n106\n\n\x0cTargeted Airstrikes Against the Islamic State of Iraq and the Levant\n\nganization. Letter on the Deployment of United States Forces in Beirut,\nLebanon, 2 Pub. Papers of Pres. Ronald Reagan at 1078\xe2\x80\x9379 (1982). And\nin his remarks to the Nation on the deployment, the President emphasized\nthe \xe2\x80\x9cirreversible commitment\xe2\x80\x9d of the United States \xe2\x80\x9cto the survival and\nterritorial integrity of friendly states.\xe2\x80\x9d Address to the Nation on United\nStates Policy for Peace in the Middle East (Sept. 1, 1982), 2 Pub. Papers\nof Pres. Ronald Reagan 1093, 1093 (1982). 10\nThe next year, when Grenada experienced widespread anarchy and violence after a \xe2\x80\x9cRevolutionary Military Council\xe2\x80\x9d assassinated the Prime\nMinister and several other government officials and seized political\npower, President Reagan authorized the deployment of nearly 2,000 U.S.\ntroops to invade the island, supported by the U.S. Air Force and Navy.\nSee Conyers v. Reagan, 765 F.2d 1124, 1125\xe2\x80\x9326 (D.C. Cir. 1985); Richard F. Grimmet, Cong. Research Serv., R42699, The War Powers Resolution: After Thirty-Eight Years 15 (Sept. 24, 2012) (\xe2\x80\x9cWar Powers Resolution\xe2\x80\x9d). The President noted in oral remarks that he had \xe2\x80\x9creceived an\nurgent, formal request\xe2\x80\x9d from the Organization of Eastern Caribbean\nStates (\xe2\x80\x9cOECS\xe2\x80\x9d), of which Grenada was a member, \xe2\x80\x9cto assist in a joint\neffort to restore order and democracy on the island of Grenada.\xe2\x80\x9d Remarks\nof the President and Prime Minister Eugenia Charles of Dominica Announcing the Deployment of United States Forces in Grenada (Oct. 25,\n1983), 2 Pub. Papers of Pres. Ronald Reagan 1505, 1505 (1983). 11 Presi10 The U.S. troops formed part of a multinational force that was sent to the country on\nmultiple occasions beginning in August 1982 to \xe2\x80\x9cfacilitate the restoration of Lebanese\nGovernment sovereignty and authority\xe2\x80\x9d and \xe2\x80\x9cthereby further the efforts of the Government of Lebanon to assure the safety of persons in the area and bring to an end the\nviolence\xe2\x80\x9d in the region. Letter to the Speaker of the House and President Pro Tempore of\nthe Senate Reporting on United States Participation in the Multinational Force in Lebanon (Sept. 29, 1982), 2 Pub. Papers of Pres. Ronald Reagan 1238, 1238 (1982). Although\nPresident Reagan indicated repeatedly that the troops would not engage in hostilities\nexcept in self-defense, the ongoing hostilities in the country resulted in the deaths of\nnumerous U.S. troops, and President Reagan ultimately received legislative authorization\nfor continuing the operations beyond October 1983. See Richard F. Grimmet, Cong.\nResearch Serv., R42699, The War Powers Resolution: After Thirty-Eight Years 13\xe2\x80\x9315\n(Sept. 24, 2012); Multinational Force in Lebanon Resolution, Pub. L. No. 98-119, 97 Stat.\n805 (1983).\n\nIn addition, the Governor-General of Grenada\xe2\x80\x94described by the former U.S. ambassador to the Eastern Caribbean as the \xe2\x80\x9csole legitimate source of authority on the island\xe2\x80\x9d\xe2\x80\x94\n11\n\n107\n\n\x0c38 Op. O.L.C. 82 (2014)\n\ndent Reagan also made clear that, along with protecting American citizens trapped in Grenada, the mission was intended \xe2\x80\x9cto forestall further\nchaos\xe2\x80\x9d and \xe2\x80\x9cto assist in the restoration of conditions of law and order and\nof governmental institutions to the island of Grenada.\xe2\x80\x9d Id. at 1506. The\nPresident\xe2\x80\x99s letter to Congress, transmitted \xe2\x80\x9cconsistent with the War\nPowers Resolution,\xe2\x80\x9d similarly indicated that, pursuant to his \xe2\x80\x9cconstitutional authority with respect to the conduct of foreign relations and as\nCommander-in-Chief,\xe2\x80\x9d he had authorized military action because the\nOECS, \xe2\x80\x9cconcerned by the deteriorating conditions in [its] member State\nof Grenada,\xe2\x80\x9d had \xe2\x80\x9crequested the immediate cooperation of a number of\nfriendly countries\xe2\x80\x9d in an effort to \xe2\x80\x9crestore order,\xe2\x80\x9d as well as to \xe2\x80\x9cprotect[]\nthe lives of the United States citizens\xe2\x80\x9d there. Letter to the Speaker of the\nHouse and the President Pro Tempore of the Senate on the Deployment\nof United States Forces in Grenada (Oct. 25, 1983), 2 Pub. Papers of\nPres. Ronald Reagan 1512, 1512\xe2\x80\x9313 (1983).\nSimilarly, President George H.W. Bush authorized the use of military\nforce in the Philippines in 1989 when military leaders seized an air force\nbase, attacked government facilities, and bombed the presidential palace\nas part of a coup attempt. Letter to the Speaker of the House of Representatives and the President Pro Tempore of the Senate on United States\nMilitary Assistance to the Philippines (Dec. 2, 1989), 2 Pub. Papers of\nPres. George Bush 1622, 1622\xe2\x80\x9323 (1989). After the President of the\nPhilippines \xe2\x80\x9cformally requested limited U.S. military assistance to support\nher forces as they attempted to put down the coup,\xe2\x80\x9d President Bush, acting\n\xe2\x80\x9cpursuant to [his] constitutional authority with respect to the conduct of\nforeign relations and as Commander in Chief,\xe2\x80\x9d authorized U.S. military\naircraft to \xe2\x80\x9cestablish a protective cover . . . to prevent rebel aircraft from\ntaking off.\xe2\x80\x9d Id. at 1623. Although \xe2\x80\x9c[n]o rebel aircraft attempted to take\n\nappealed to the United States for help, adding \xe2\x80\x9cweight to the legal and political basis for\nthe invasion.\xe2\x80\x9d U.S. Military Actions in Grenada: Implications for U.S. Policy in the\nEastern Caribbean: Hearings Before the Subcomm. on Int\xe2\x80\x99l Sec. and Scientific Affairs\n& on W. Hemisphere Affairs of the H. Comm. on Foreign Affairs, 98th Cong. 59 (1988)\n(statement of Sally A. Shelton); see also Radio Address to the Nation on International\nStability (Oct. 26, 1985), 2 Pub. Papers of Pres. Ronald Reagan 1294, 1294 (1985)\n(noting on the second anniversary of the operation that \xe2\x80\x9cGrenada\xe2\x80\x99s Governor-General\xe2\x80\x9d\nhad \xe2\x80\x9cappealed for [the United States\xe2\x80\x99s] help to restore order in his country, threatened by\nthe machinery of dictatorship\xe2\x80\x9d).\n\n108\n\n\x0cTargeted Airstrikes Against the Islamic State of Iraq and the Levant\n\noff, and U.S. aircraft did not fire,\xe2\x80\x9d President Bush made clear in his War\nPowers Resolution notification to Congress that he would be \xe2\x80\x9cprepared\n. . . to take additional [military] actions\xe2\x80\x9d not only \xe2\x80\x9cto protect the lives of\nAmericans\xe2\x80\x9d but also, \xe2\x80\x9cif requested, to provide further assistance to the\ngovernment of the Philippines,\xe2\x80\x9d in recognition of the fact that the United\nStates had \xe2\x80\x9cworked . . . over the years to provide assistance to the democratically elected government of the Philippines.\xe2\x80\x9d Id.\nAlong similar lines, after Iraq had invaded Kuwait and was threatening\nSaudi Arabia in 1990, and the \xe2\x80\x9cSaudi Government had requested [the]\nhelp\xe2\x80\x9d of the United States, President Bush deployed the military to \xe2\x80\x9cassist\nthe Saudi Arabian Government in the defense of its homeland.\xe2\x80\x9d Address\nto the Nation Announcing the Deployment of United States Armed Forces\nto Saudi Arabia (Aug. 8, 1990), 2 Pub. Papers of Pres. George Bush 1107,\n1107\xe2\x80\x9308 (1990). In his address to the Nation, President Bush explained\nthat his decision \xe2\x80\x9cgr[e]w[] out of the longstanding friendship and security\nrelationship between the United States and Saudi Arabia\xe2\x80\x9d and out of the\nprinciple that \xe2\x80\x9cAmerica will stand by her friends.\xe2\x80\x9d Id. at 1109. And in his\nWar Powers Resolution report to Congress, the President indicated that\nthe U.S. troops would remain \xe2\x80\x9cso long as their presence is . . . desired by\nthe Saudi government to enhance [its] capability . . . to defend the Kingdom.\xe2\x80\x9d Letter to Congressional Leaders on the Deployment of United\nStates Armed Forces to Saudi Arabia and the Middle East (Aug. 9, 1990),\n2 Pub. Papers of Pres. George Bush 1116, 1116 (1990). President Bush\nalso stated that he had taken these actions \xe2\x80\x9cpursuant to [his] authority to\nconduct our foreign relations and as Commander in Chief.\xe2\x80\x9d Id.\nFinally, as referenced above, President Clinton, in coordination with\nthe deposed, democratically elected President of Haiti, authorized military action in Haiti without congressional approval to force the military\ndictators from power and \xe2\x80\x9crestore Haiti\xe2\x80\x99s legitimate, democratically\nelected government.\xe2\x80\x9d Address to the Nation on Haiti (Sept. 15, 1994),\n2 Pub. Papers of Pres. William J. Clinton 1558, 1558\xe2\x80\x9360 (1994); see also\nWar Powers Resolution at 37\xe2\x80\x9339. Although an eleventh-hour agreement\nwith the dictators reduced the risk of direct hostilities, President Clinton\nhad authorized a hostile military invasion involving 20,000 troops, to be\ndeployed in conjunction with an international coalition. See 1994 Haiti\nDeployment, 18 Op. O.L.C. at 174 n.1, 179 n.10; War Powers Resolution\n\n109\n\n\x0c38 Op. O.L.C. 82 (2014)\n\nat 38; Address to the Nation on Haiti (Sept. 18, 1994), 2 Pub. Papers of\nPres. William J. Clinton 1571, 1571\xe2\x80\x9372 (1994). 12\nIn light of this historical practice and our precedent, we believe the\nPresident had the constitutional authority to rely on a national interest in\nsupporting Iraq, a strategic partner, in ordering targeted airstrikes against\nISIL without congressional approval. Although the President\xe2\x80\x99s support to\nthe Iraqi government was limited to five particular operations that also\nserved other national interests, see supra Part II.A.1 and infra Part II.A.3,\nthe Iraqi government requested the assistance of the United States with\nrespect to all of those operations, and the President determined that agreeing to these requests would materially aid Iraq in its \xe2\x80\x9congoing campaign\nagainst [ISIL].\xe2\x80\x9d August 17 Report to Congress; see August 8 Report to\nCongress (noting the Erbil operation would help \xe2\x80\x9cstop[] the current advance on Erbil\xe2\x80\x9d); September 1 Report to Congress (noting the action had\nbeen taken \xe2\x80\x9cat the request of the Iraqi government\xe2\x80\x9d); September 8 Report\nto Congress (noting the Haditha Dam airstrikes were undertaken \xe2\x80\x9cin\ncoordination with and at the request of the Iraqi Government\xe2\x80\x9d to support\n\xe2\x80\x9cIraqi forces in their efforts to retain control of and defend [their] critical\ninfrastructure\xe2\x80\x9d). ISIL, moreover, presents an acute threat to the Iraqi\nGovernment\xe2\x80\x99s control over its country, to law and order within the country, and to the safety of Iraq\xe2\x80\x99s citizens. See supra Part I. President\nObama\xe2\x80\x99s actions in assisting the Iraqi government\xe2\x80\x99s campaign against\nISIL thus mirror military action taken by past Presidents to suppress\ninsurrection, maintain order, or restore a rightful government upon an\nally\xe2\x80\x99s or strategic partner\xe2\x80\x99s request, or to answer a friendly government\xe2\x80\x99s\nrequest for help in defending itself from attack.\n12 Responding to an ally\xe2\x80\x99s or partner\xe2\x80\x99s request for assistance bears some resemblance to obtaining the consent of a foreign government for using armed force in its\nterritory, which is a justification under international law for the use of force in such\ncircumstances. But even leaving aside the differences between responding to an affirmative request from an ally or partner and seeking consent from a country for military action\nthe United States seeks to initiate, nothing in the presidential statements discussed in the\ntext suggests that these Presidents were invoking assistance to an ally or partner primarily\nas an international law justification for their actions. Indeed, as we noted in the text,\nPresidents have included assistance to allies or strategic partners as a reason for taking\nmilitary action in reports sent to Congress \xe2\x80\x9cconsistent with the War Powers Resolution,\xe2\x80\x9d\nwhich requires an explanation of the domestic \xe2\x80\x9cconstitutional and legislative authority\xe2\x80\x9d\npursuant to which the President has authorized military action. 50 U.S.C. \xc2\xa7 1543(a).\n\n110\n\n\x0cTargeted Airstrikes Against the Islamic State of Iraq and the Levant\n\nIn addition, Iraq\xe2\x80\x94like many of the allies or partners Presidents assisted\nin the examples described above\xe2\x80\x94is a country of particular strategic\nimportance to the United States and one that the United States has aided\nin the past and has made an ongoing commitment to assist. The use of\nmilitary force to assist allies in general is consistent with the current U.S.\nnational security strategy, which expressly states that \xe2\x80\x9c[t]he foundation of\nthe United States, regional, and global security will remain America\xe2\x80\x99s\nrelations with our allies, and our commitment to their security is unshakable.\xe2\x80\x9d National Security Strategy 41 (May 2010), http://nssarchive.us/\nNSSR/2010.pdf. And with respect to Iraq in particular, the United States\nhas a recent history of providing assistance, including military assistance\nauthorized by Congress, as Iraq works to establish itself as a stable country in a volatile and strategically important region. See Iraq AUMF; supra\nPart I (discussing surge). Although the United States withdrew its troops\nfrom Iraq in 2011, it simultaneously committed to \xe2\x80\x9ccontinue to foster\nclose cooperation concerning defense and security arrangements\xe2\x80\x9d and to\n\xe2\x80\x9cimprove and strengthen the security and stability in Iraq.\xe2\x80\x9d Strategic\nFramework Agreement at 2\xe2\x80\x933; see also U.S. Dep\xe2\x80\x99t of Def., News Transcript, Joint Press Conference by Secretary Hagel and Minister Johnston\nin Sydney, Australia (Aug. 11, 2014) (Secretary Hagel), https://dod.\ndefense.gov/News/Transcripts/Transcript-View/Article/606908/jointpress-conference-by-secretary-hagel-and-minister-johnston-in-sydneyaustr (\xe2\x80\x9c[T]he [P]resident has also made it clear we\xe2\x80\x99re going to support the\nIraqi security forces in\xe2\x80\x94in every way we can, as they request assistance\nthere.\xe2\x80\x9d). In addition, as the President has explained, a stable Iraq will\npermit the United States \xe2\x80\x9cto craft [a] . . . joint counterterrorism strategy\xe2\x80\x9d\nwith \xe2\x80\x9cthe Iraqi Government [and] also with regional actors . . . beyond\nthe Middle East.\xe2\x80\x9d Remarks on the Situations in Iraq and Ferguson, Missouri, and an Exchange with Reporters, Daily Comp. Pres. Doc. No.\nDCPD201400615, at 4 (Aug. 18, 2014); see also John Kerry, U.S. Dep\xe2\x80\x99t\nof State, Press Statement, U.S. Welcomes Important Step in Iraq\xe2\x80\x99s Government Formation Process (Aug. 11, 2014), https://2009-2017.state.gov/\nsecretary/remarks/2014/08/230506.htm (emphasizing that \xe2\x80\x9c[t]he United\nStates will continue to . . . stand with the Iraqi people in their fight\nagainst terrorism\xe2\x80\x9d). The President thus had the constitutional authority to\nrely on a national interest in supporting Iraq, a strategic partner, in ordering targeted airstrikes against ISIL without congressional approval.\n111\n\n\x0c38 Op. O.L.C. 82 (2014)\n\n3.\nThe third national interest cited by President Obama\xe2\x80\x94relevant in particular to the airstrikes near Mount Sinjar, the Mosul Dam, Amirli, and the\nHaditha Dam\xe2\x80\x94is an interest in averting humanitarian catastrophe. See\nPresident Obama August 7 Statement (citing the need to prevent a \xe2\x80\x9cpotential act of genocide\xe2\x80\x9d at Mount Sinjar); August 8 Report to Congress\n(explaining that the airstrikes around Mount Sinjar were authorized to\n\xe2\x80\x9cprotect the civilians trapped there\xe2\x80\x9d); August 17 Report to Congress\n(noting the failure of the Mosul Dam could \xe2\x80\x9cthreaten the lives of large\nnumbers of civilians\xe2\x80\x9d); September 1 Report to Congress (noting that the\nAmirli airstrikes would \xe2\x80\x9caddress the emerging humanitarian crisis and\nprotect the civilians trapped\xe2\x80\x9d in that town); September 8 Report to Congress (noting the danger to \xe2\x80\x9clarge numbers of Iraqi civilians\xe2\x80\x9d). We believe\nit was reasonable for the President, in exercising his constitutional authority as Commander in Chief and Chief Executive, to rely on this humanitarian interest, at least in combination with a national interest in protecting American citizens and property or supporting a strategic partner, as a\nbasis for conducting military action without prior authorization from\nCongress.\nThe United States places great importance on protecting innocent lives\nand reducing suffering around the world. In a recent presidential directive,\nfor example, President Obama recognized that \xe2\x80\x9c[p]reventing mass atrocities and genocide is a core national security interest and a core moral\nresponsibility of the United States.\xe2\x80\x9d Office of the Press Secretary, The\nWhite House, PSD-10, Presidential Study Directive on Mass Atrocities\n(Aug. 4, 2011), https://obamawhitehouse.archives.gov/the-press-office/\n2011/08/04/presidential-study-directive-mass-atrocities. Consistent with\nthat interest, the United States has ratified and implemented, through the\nGenocide Convention Implementation Act of 1987, Pub. L. No. 100-606,\n102 Stat. 3045 (1988), the Convention on the Prevention and Punishment\nof the Crime of Genocide, Dec. 9, 1948, 78 U.N.T.S. 277, which affirms\nthat the contracting parties will \xe2\x80\x9cundertake to prevent\xe2\x80\x9d genocide and\nrecognizes that \xe2\x80\x9cin order to liberate mankind from such an odious\nscourge, international co-operation is required,\xe2\x80\x9d id. pmbl., art. I; see also\nApplication of Convention on Prevention and Punishment of Crime of\nGenocide (Bosn. & Herz. v. Serb. & Montenegro), Judgment, 2007 I.C.J.\n47, \xc2\xb6 165 (Feb. 26) (finding that \xe2\x80\x9cthe contracting parties have a direct\n112\n\n\x0cTargeted Airstrikes Against the Islamic State of Iraq and the Levant\n\nobligation to prevent genocide\xe2\x80\x9d). The United States has also made clear\nthat preventing mass atrocities may in some instances require the use of\nmilitary force. See, e.g., National Security Strategy 48 (May 2010) (\xe2\x80\x9cIn\nthe event that prevention fails, the United States will work both multilaterally and bilaterally to mobilize diplomatic, humanitarian, financial,\nand\xe2\x80\x94in certain instances\xe2\x80\x94military means to prevent and respond to\ngenocide and mass atrocities.\xe2\x80\x9d).\nConsistent with these policies, Presidents have cited humanitarian concerns as an important national interest supporting multiple U.S. military\ndeployments in the past, including those in Haiti in 1994, the former\nYugoslavia in 1995, and Libya in 2011. See, e.g., Letter to Congressional\nLeaders on Deployment of United States Armed Forces to Haiti (Sept. 18,\n1994), 2 Pub. Papers of Pres. William J. Clinton 1572, 1572 (1994) (\xe2\x80\x9cThe\ndeployment of U.S. Armed Forces into Haiti is justified by United States\nnational security interests\xe2\x80\x9d including \xe2\x80\x9cstop[ping] the brutal atrocities that\nthreaten tens of thousands of Haitians[.]\xe2\x80\x9d); Letter to Congressional Leaders on the Deployment of United States Military Forces for Implementation of the Balkan Peace Process (Dec. 21, 1995), 2 Pub. Papers of Pres.\nWilliam J. Clinton 1917, 1917\xe2\x80\x9318 (1995) (\xe2\x80\x9cI authorized these deployments . . . as part of our commitment to secure the peace and halt the\ntragic loss of life in the former Yugoslavia.\xe2\x80\x9d); Office of the Press Secretary, The White House, Letter from the President Regarding the Commencement of Operations in Libya (Mar. 21, 2011) (\xe2\x80\x9cLibya Report to\nCongress\xe2\x80\x9d), https://obamawhitehouse.archives.gov/the-press-office/2011/\n03/21/letter-president-regarding-commencement-operations-libya (notifying Congress of the commencement of operations \xe2\x80\x9cto prevent a humanitarian catastrophe\xe2\x80\x9d).\nIndeed, in some past military deployments, a humanitarian purpose appears to have been one of the primary reasons for the President\xe2\x80\x99s decision\nto act. In March 1999, for example, when President Clinton, together with\ncertain NATO allies, launched airstrikes against the Serbian forces and\nmilitary infrastructure of the Federal Republic of Yugoslavia to protect\ncivilians in Kosovo, humanitarian purposes were the central focus of the\nmission. As President Clinton weighed his military options in the region,\nhe stated that \xe2\x80\x9c[o]ur objective in Kosovo remains clear: to stop the killing\nand achieve a durable peace that restores Kosovars to self-government.\xe2\x80\x9d\nRemarks on the Situation in Kosovo (Mar. 22, 1999), 1 Pub. Papers of\n113\n\n\x0c38 Op. O.L.C. 82 (2014)\n\nPres. William J. Clinton 426, 426 (1999). And when he announced the\nairstrikes, President Clinton notified Congress that he was doing so for the\nprincipal purposes of emphasizing to Serbian leaders \xe2\x80\x9cthe imperative of\nreversing course\xe2\x80\x9d in their offensive against civilians in Kosovo; \xe2\x80\x9cto deter\nan even bloodier offensive against innocent civilians in Kosovo; and, if\nnecessary, to seriously damage the Serbian military\xe2\x80\x99s capacity to harm the\npeople of Kosovo.\xe2\x80\x9d Letter to Congressional Leaders Reporting on Airstrikes Against Serbian Targets in the Federal Republic of Yugoslavia\n(Serbia and Montenegro) (Mar. 26, 1999), 1 Pub. Papers of Pres. William\nJ. Clinton 459, 459 (1999). 13 Two weeks later, President Clinton reaffirmed these objectives when he stated that he would \xe2\x80\x9ccontinue to intensify our actions to achieve the objectives . . . described\xe2\x80\x9d in the previous\nreport to Congress, and to \xe2\x80\x9csupport the international relief efforts being\nconducted in the region.\xe2\x80\x9d Letter to Congressional Leaders Reporting on\nAirstrikes Against Serbian Targets in the Federal Republic of Yugoslavia\n(Serbia and Montenegro) (Apr. 7, 1999), 1 Pub. Papers of Pres. William J.\nClinton 516, 516 (1999). The President underscored the humanitarian\nnature of the operation by ordering the deployment of forces to Albania\nand Macedonia \xe2\x80\x9cto support humanitarian disaster relief operations for the\nKosovar refugees.\xe2\x80\x9d Id. And shortly thereafter, he described his actions in\nKosovo and surrounding areas as an effort \xe2\x80\x9cto stand against ethnic cleansing, save lives, and bring peace in Kosovo.\xe2\x80\x9d Remarks Following a Meeting with Congressional Leaders and an Exchange with Reporters (Apr.\n13, 1999), 1 Pub. Papers of Pres. William J. Clinton 546, 546 (1999).\nSimilarly, President George H.W. Bush\xe2\x80\x99s deployment of more than\n25,000 troops to war-torn and divided Somalia during a widespread famine in 1992 was undertaken \xe2\x80\x9cto address a major humanitarian calamity,\navert related threats to international peace and security, and protect the\nsafety of Americans and others engaged in relief operations.\xe2\x80\x9d Letter to\nCongressional Leaders on the Situation in Somalia (Dec. 10, 1992),\n2 Pub. Papers of Pres. George Bush 2179, 2179\xe2\x80\x9380 (1992\xe2\x80\x9393); see Address to the Nation on the Situation in Somalia (Dec. 4, 1992), 2 Pub.\nPapers of Pres. George Bush 2174, 2175 (1992\xe2\x80\x9393) (\xe2\x80\x9cIt\xe2\x80\x99s now clear that\n13 Although the notification to Congress also mentions other concerns\xe2\x80\x94including concerns about regional stability that we cited in our Libya opinion, see Military Force in\nLibya, 35 Op. O.L.C. at 34\xe2\x80\x9335\xe2\x80\x94the notification makes clear that the mission was principally a humanitarian one.\n\n114\n\n\x0cTargeted Airstrikes Against the Islamic State of Iraq and the Levant\n\nmilitary support is necessary to ensure the safe delivery of the food Somalis need to survive.\xe2\x80\x9d). In his address to the Nation, President Bush said:\n\xe2\x80\x9cLet me be very clear: Our mission is humanitarian[.]\xe2\x80\x9d Address to the\nNation on Situation in Somalia, 2 Pub. Papers of Pres. George Bush at\n2175 (1992\xe2\x80\x9393); see also Michael R. Gordon, Mission to Somalia: U.S. Is\nSending Large Force as Warning to Somali Clans, N.Y. Times, Dec. 5,\n1992, at 5 (noting the Pentagon had issued an \xe2\x80\x9cofficial \xe2\x80\x98mission statement\xe2\x80\x99 for the operation, which underscored that the purpose of the intervention is to provide humanitarian aid\xe2\x80\x9d). The mission\xe2\x80\x99s purpose was thus\nnot simply to protect the American citizens already in Somalia and to\n\xe2\x80\x9cfacilitate the safe and orderly deployment of U.N. peacekeeping forces in\nSomalia,\xe2\x80\x9d but also \xe2\x80\x9cto restore the flow of humanitarian relief to those\nareas of Somalia most affected by famine and disease.\xe2\x80\x9d Military Forces in\nSomalia, 16 Op. O.L.C. at 6. In explaining why such an expansive U.S.\nmilitary action was needed, President Bush emphasized that \xe2\x80\x9c[o]nly the\nUnited States has the global reach to place a large security force on the\nground in such a distant place quickly and efficiently and thus save thousands of innocents from death.\xe2\x80\x9d Address to the Nation on the Situation in\nSomalia, 2 Pub. Papers of Pres. George Bush at 2175 (1992\xe2\x80\x9393). President Clinton also reiterated the humanitarian nature of the Somalia mission when the deployment ended. See Remarks on Welcoming Military\nPersonnel Returning from Somalia (May 5, 1993), 1 Pub. Papers of Pres.\nWilliam J. Clinton 565, 565 (1993) (noting it was \xe2\x80\x9cthe largest humanitarian relief operation in history\xe2\x80\x9d and that \xe2\x80\x9ctens of thousands would have\ndied\xe2\x80\x9d if the U.S. had not acted).\nWhile Presidents have often stressed the humanitarian purposes underlying military actions taken abroad, this Office\xe2\x80\x99s analysis of these actions\nhas frequently emphasized other relevant national interests, such as\nregional stability or the protection of American lives. See, e.g., Military\nForce in Libya, 35 Op. O.L.C. at 27 (emphasizing \xe2\x80\x9cimportant U.S. interests in preventing instability in the Middle East and preserving the credibility and effectiveness of the United Nations Security Council\xe2\x80\x9d); Proposed Bosnia Deployment, 19 Op. O.L.C. at 332\xe2\x80\x9333 (emphasizing support for the United Nations and the North Atlantic Treaty Organization,\nas well as the need to preserve regional stability); 1994 Haiti Deployment, 18 Op. O.L.C. at 177\xe2\x80\x9379 (highlighting the fact that the operation\ntook place with the consent of the legitimate government). But despite\n115\n\n\x0c38 Op. O.L.C. 82 (2014)\n\nfocusing on other national interests, our opinions have often expressly\nnoted the humanitarian purpose of those deployments. And in so doing,\nwe have never suggested that the goal of preventing humanitarian catastrophes could not be an important national interest supporting the use of\nmilitary force abroad. See Military Force in Libya, 35 Op. O.L.C. at 23,\n35; Proposed Bosnia Deployment, 19 Op. O.L.C. at 329; 1994 Haiti\nDeployment, 18 Op. O.L.C. at 177.\nWe have also more than once suggested that, when a military deployment is undertaken in part to protect American citizens abroad, its scope\ncan legitimately be expanded to achieve broader humanitarian objectives.\nIn analyzing the legality of the deployment of U.S. forces to Somalia, for\nexample, we began with the national interest in the protection of U.S.\npersons, see Military Forces in Somalia, 16 Op. O.L.C. at 6, but then went\non to determine that the President\xe2\x80\x99s power to deploy forces abroad was\nnot \xe2\x80\x9cstrictly limited to the protection of American citizens,\xe2\x80\x9d id. at 11.\n\xe2\x80\x9cPast military interventions,\xe2\x80\x9d we explained, \xe2\x80\x9cextended to the protection of\nforeign nationals\xe2\x80\x9d and \xe2\x80\x9cprovide precedent for action to protect endangered\nSomalians and other non-United States citizens.\xe2\x80\x9d Id. (citing, among other\nexamples, President Johnson\xe2\x80\x99s ordering of military intervention in the\nDominican Republic to \xe2\x80\x9cpreserve the lives of American citizens and\ncitizens of a good many other nations\xe2\x80\x9d and President McKinley\xe2\x80\x99s dispatch\nof 5,000 troops to China during the Boxer Rebellion to rescue the besieged foreign legations, including both U.S. and foreign contingents, in\nBeijing (internal quotation marks omitted)); see also Right to Protect at\n65 (troops landed in Uruguay in 1868 \xe2\x80\x9cfor the protection of foreign residents\xe2\x80\x9d generally during an insurrection); id. at 120 (troops sent to Nicaragua in 1912 to help the Nicaraguan government protect American citizens\nand \xe2\x80\x9call inhabitants\xe2\x80\x9d of the country during an attempted revolution (internal quotation marks omitted)). We reached a similar conclusion in 2004,\ndetermining that \xe2\x80\x9c[w]hen the armed forces [we]re deployed [to Haiti] for\nthe protection of American citizens and property, their mission once\ndeployed\xe2\x80\x9d did not need to be \xe2\x80\x9cso narrowly limited,\xe2\x80\x9d but rather could\nextend to the protection of Haitians and other innocent civilians. 2004\nHaiti Deployment, 28 Op. O.L.C. at 32. 14\nAlthough the engagements in Somalia and Haiti had the reinforcement of U.N. resolutions authorizing force, our opinions did not suggest that a President could expand the\n14\n\n116\n\n\x0cTargeted Airstrikes Against the Islamic State of Iraq and the Levant\n\nIn light of these precedents, we believe it was reasonable for the President to rely on a national interest in preventing humanitarian catastrophe,\nat least in combination with an interest in protecting Americans or supporting an ally or strategic partner, as a justification for conducting\nairstrikes against ISIL\xe2\x80\x99s positions around Mount Sinjar, the Mosul Dam,\nAmirli, and the Haditha Dam. As discussed above, the President determined that the situation on Mount Sinjar presented \xe2\x80\x9cthe prospect of\nviolence on a horrific scale,\xe2\x80\x9d involving \xe2\x80\x9ca potential act of genocide\xe2\x80\x9d that\nthe United States had \xe2\x80\x9cunique capabilities to help avert.\xe2\x80\x9d President\nObama August 7 Statement; cf. Address to the Nation on the Situation in\nSomalia, 2 Pub. Papers of Pres. George Bush at 2175 (1992\xe2\x80\x9393) (noting\nthat, in Somalia, \xe2\x80\x9c[o]nly the United States\xe2\x80\x9d could \xe2\x80\x9csave thousands of\ninnocents from death\xe2\x80\x9d). This concern was shared by U.N. officials, who\nwarned that a \xe2\x80\x9chumanitarian tragedy [wa]s unfolding in Sinjar.\xe2\x80\x9d UN\nDaily News, UN Warns of \xe2\x80\x9cHumanitarian Tragedy\xe2\x80\x9d as Militants Seize\nTown in Northern Iraq (Aug. 4, 2014), http://www.un.org/News/dh/pdf/\nenglish/2014/04082014.pdf; see also Security Council August 5 Press\nRelease (expressing \xe2\x80\x9cdeep concern\xe2\x80\x9d about the thousands of Iraqis, many\nfrom the Yezidi community, displaced by ISIL and \xe2\x80\x9cin urgent need of\nhumanitarian assistance\xe2\x80\x9d). Similarly, the failure of either the Mosul Dam\nor the Haditha Dam could have unleashed flood waves capable of killing\nlarge numbers of innocent civilians and endangering or displacing hundreds of thousands of others, in cities from Mosul to Baghdad. See August 17 Report to Congress; Mosul Dam Letter; September 8 Report to\nCongress; NSC September 7 Statement; see also Ellison, An Unprecedented Task, 63 Int\xe2\x80\x99l Water Power & Dam Construction at 50\xe2\x80\x9351 (noting\nthe failure of the Mosul Dam could potentially kill a half-million civilians). And in Amirli, the President likewise identified an \xe2\x80\x9cemerging\nhumanitarian crisis\xe2\x80\x9d caused by ISIL\xe2\x80\x99s siege of the town, September 1\nReport to Congress, an assessment that reflected the State Department\xe2\x80\x99s\nscope of a mission for humanitarian reasons only if a U.N. resolution was in effect. See\n2004 Haiti Deployment, 28 Op. O.L.C. at 33; Military Forces in Somalia, 16 Op. O.L.C.\nat 7. Moreover, although the U.N. Security Council has not passed a resolution authorizing the use of force in Iraq, it has called on the international community \xe2\x80\x9cto support the\nGovernment and people of Iraq and to do all it can to help alleviate the suffering of the\npopulation affected by the current conflict in Iraq.\xe2\x80\x9d Security Council August 7 Press\nRelease.\n\n117\n\n\x0c38 Op. O.L.C. 82 (2014)\n\nconcern about the \xe2\x80\x9cdire conditions for the mainly Turkmen population,\xe2\x80\x9d\nState Department August 28 Daily Press Briefing, and that was consistent\nwith calls by U.N. officials for \xe2\x80\x9cimmediate action\xe2\x80\x9d to alleviate the \xe2\x80\x9cdesperate\xe2\x80\x9d and \xe2\x80\x9cinhuman conditions\xe2\x80\x9d in Amirli and prevent a \xe2\x80\x9cpossible\nimminent massacre\xe2\x80\x9d of the town\xe2\x80\x99s citizens, see UN News, Iraqi Civilians Suffering \xe2\x80\x9cHorrific\xe2\x80\x9d Persecution, Ethnic Cleansing\xe2\x80\x94UN Rights\nChief (Aug. 25, 2014), https://news.un.org/en/story/2014/08/475812iraqi-civilians-suffering-horrific-persecution-ethnic-cleansing-un-rightschief; UN News, Iraq: UN Envoy Calls for Immediate Action to Avert\nPossible \xe2\x80\x9cMassacre\xe2\x80\x9d in Northern Town (Aug. 23, 2014), https://news.un.\norg/en/story/2014/08/475762-iraq-un-envoy-calls-immediate-action-avertpossible-massacre-northern-town. In all four instances, U.S. airstrikes\nwere designed to help Iraqi and aligned forces prevent the humanitarian\ncatastrophes that were unfolding, either by mitigating ISIL\xe2\x80\x99s threat, permitting the delivery of humanitarian aid, or both. Given these circumstances, we think the President reasonably invoked a national interest in\npreventing humanitarian catastrophe, in combination with a national\ninterest in protecting American citizens and property or supporting a\nstrategic partner, to justify deploying military forces abroad. 15\nB.\nWe next consider whether the anticipated nature, scope, and duration of\nthe airstrike operations discussed in this opinion were sufficiently limited\nso as not to require prior congressional approval under the Declaration of\nWar Clause. As we have previously explained, determining whether a\nmilitary engagement amounts to a \xe2\x80\x9cwar\xe2\x80\x9d for constitutional purposes\ninvolves a \xe2\x80\x9cfact-specific assessment of the \xe2\x80\x98anticipated nature, scope, and\nduration\xe2\x80\x99 of the planned military operations,\xe2\x80\x9d analyzed in light of the\napplicable historical precedent. Military Force in Libya, 35 Op. O.L.C. at\n31 (quoting 1994 Haiti Deployment, 18 Op. O.L.C. at 179). Here, we\n\nOur conclusion addresses only the President\xe2\x80\x99s domestic legal authority to engage in\nsuch military intervention without prior congressional approval. We do not address the\nvalidity of humanitarian intervention as a justification for the use of force under international law. See, e.g., Paul R. Williams et al., Preventing Mass Atrocity Crimes: The Responsibility to Protect and the Syria Crisis, 45 Case W. Res. J. Int\xe2\x80\x99l L. 473, 479\xe2\x80\x9380 (2012)\n(noting the controversy surrounding humanitarian intervention in international law).\n15\n\n118\n\n\x0cTargeted Airstrikes Against the Islamic State of Iraq and the Levant\n\nbelieve the anticipated nature, scope, and duration of the operations at\nissue were sufficiently limited so as not to constitute a \xe2\x80\x9cwar.\xe2\x80\x9d\nMilitary actions generally rise to the level of \xe2\x80\x9cwar\xe2\x80\x9d for constitutional\npurposes only when they involve \xe2\x80\x9cprolonged and substantial military\nengagements, typically involving exposure of U.S. military personnel to\nsignificant risk over a substantial period.\xe2\x80\x9d Id. Certain factors reduce the\nlikelihood that a military engagement will amount to a \xe2\x80\x9cwar\xe2\x80\x9d in the constitutional sense. For example, military operations that do not include the\nintroduction of ground troops are less likely to constitute a \xe2\x80\x9cwar.\xe2\x80\x9d See id.\nat 38; Proposed Bosnia Deployment, 19 Op. O.L.C. at 333. 16 In addition,\nwe have previously suggested that where an \xe2\x80\x9coperation does not aim at\nthe conquest or occupation of territory\xe2\x80\x9d or seek to \xe2\x80\x9cimpos[e] through\nmilitary means a change in the character of the political regime,\xe2\x80\x9d the\noperation\xe2\x80\x99s more limited aims will likely reduce the risk of resistance to\nthe U.S. deployment and decrease the time needed to fulfill those aims.\nProposed Bosnia Deployment, 19 Op. O.L.C. at 332. Both the lack of\nground troops and the more limited goal of an operation also limit the\n\xe2\x80\x9cantecedent risk that United States forces\xe2\x80\x9d will \xe2\x80\x9csuffer or inflict substantial casualties as a result of the deployment.\xe2\x80\x9d 1994 Haiti Deployment, 18\nOp. O.L.C. at 179.\nConsistent with these principles, we advised in 2011 that the conduct of\nlimited airstrikes and associated support missions in Libya for the purpose\nWe do not mean to imply that contemplated deployments of ground forces\xe2\x80\x94even in\nsubstantial numbers\xe2\x80\x94necessarily constitute \xe2\x80\x9cwars\xe2\x80\x9d for constitutional purposes. For\nexample, in 1994, we concluded that the planned deployment of 20,000 troops to Haiti to\noust military dictators and reinstall the legitimate government was not a \xe2\x80\x9cwar,\xe2\x80\x9d placing\ngreat weight on \xe2\x80\x9cthe limited antecedent risk that United States forces would encounter\nsignificant armed resistance or suffer or inflict substantial casualties as a result of the\ndeployment.\xe2\x80\x9d 1994 Haiti Deployment, 18 Op. O.L.C. at 179. And in 1995, we concluded\nthat the planned deployment of about 20,000 ground troops to Bosnia and Herzegovina to\nensure compliance with a peace agreement was not a \xe2\x80\x9cwar.\xe2\x80\x9d Proposed Bosnia Deployment, 19 Op. O.L.C. at 332\xe2\x80\x9333. We acknowledged that the deployment of ground troops\nwas \xe2\x80\x9can essentially different, and more problematic, type of intervention\xe2\x80\x9d than air or\nnaval operations, because of the increased risk of casualties and the greater difficulty of\nwithdrawing ground forces, but nevertheless found that that concern was outweighed by\nthe fact that the deployment was at the invitation of warring parties to support the agreement they had reached and thus it was \xe2\x80\x9creasonably possible that little or no resistance to\nthe deployment w[ould] occur.\xe2\x80\x9d Id.\n16\n\n119\n\n\x0c38 Op. O.L.C. 82 (2014)\n\nof preventing regional instability and preserving the credibility and effectiveness of the U.N. Security Council did not amount to a \xe2\x80\x9cwar\xe2\x80\x9d in the\nconstitutional sense. Military Force in Libya, 35 Op. O.L.C. at 37\xe2\x80\x9339. The\nU.S. mission had at first targeted the Libyan regime\xe2\x80\x99s \xe2\x80\x9cair defense systems, command and control structures, and other capabilities . . . used to\nattack civilians and civilian populated areas,\xe2\x80\x9d and had then shifted to\nproviding support for a NATO-led effort to enforce a no-fly zone and\notherwise protect civilians in Libya. Id. at 25\xe2\x80\x9326 (internal quotation\nmarks omitted). We compared this operation to two prior campaigns\nconducted without prior congressional authorization\xe2\x80\x94a series of no-fly\nzone patrols and periodic airstrikes in Bosnia that had lasted for more than\ntwo years prior to the deployment of ground troops in 1995 and a twomonth NATO bombing campaign in Yugoslavia in 1999\xe2\x80\x94and concluded\nthat the operations in Libya similarly fell short of requiring a congressional declaration of war. We reached this conclusion in part based on the\nPresident\xe2\x80\x99s assurance that\xe2\x80\x94as in the air campaigns in Bosnia and Yugoslavia\xe2\x80\x94ground troops would not be deployed, which meant that \xe2\x80\x9c[t]he\nplanned operations [would] avoid[] the difficulties of withdrawal and\nrisks of escalation that may attend commitment of ground forces.\xe2\x80\x9d Id. at\n38. We also based our conclusion on the \xe2\x80\x9climited means, objectives, and\nintended duration\xe2\x80\x9d of the mission, explaining that the proposed action\n\xe2\x80\x9cdid not \xe2\x80\x98aim at the conquest or occupation of territory,\xe2\x80\x99\xe2\x80\x9d but instead was\n\xe2\x80\x9c\xe2\x80\x98in support of international efforts to protect civilians and prevent a\nhumanitarian disaster.\xe2\x80\x99\xe2\x80\x9d Id. (quoting Proposed Bosnia Deployment, 19\nOp. O.L.C. at 332; Libya Report to Congress).\nFor similar reasons, we do not believe that the operations addressed in\nthis opinion constituted a \xe2\x80\x9cwar\xe2\x80\x9d in the constitutional sense. President\nObama made clear that\xe2\x80\x94aside from a rejected proposal to use ground\ntroops to help extract the trapped Yezidis, see supra note 4\xe2\x80\x94the operations would be restricted to airstrikes and associated support missions.\n\xe2\x80\x9cAmerican combat troops,\xe2\x80\x9d the President explained, \xe2\x80\x9cwill not be returning to fight in Iraq.\xe2\x80\x9d Office of the Press Secretary, The White House,\nWeekly Address: American Operations in Iraq (Aug. 9, 2014), https://\nobamawhitehouse.archives.gov/the-press-office/2014/08/09/weeklyaddress-american-operations-iraq; see also Office of the Press Secretary,\nThe White House, Press Briefing by Principal Deputy Press Secretary\nEric Schultz and Deputy National Security Advisor Ben Rhodes (Aug.\n120\n\n\x0cTargeted Airstrikes Against the Islamic State of Iraq and the Levant\n\n13, 2014), https://obamawhitehouse.archives.gov/the-press-office/2014/\n08/13/press-briefing-principal-deputy-press-secretary-eric-schultz-anddeputy- (noting, in response to questions about the possibility of ground\ntroops assisting in an evacuation of Mount Sinjar, that President Obama\nhad \xe2\x80\x9cruled out . . . reintroducing U.S. forces into combat, on the ground,\nin Iraq\xe2\x80\x9d). Thus, like our efforts in Libya, these operations were designed\nto \xe2\x80\x9cavoid the difficulties of withdrawal and risks of escalation that may\nattend commitment of ground forces.\xe2\x80\x9d Military Force in Libya, 35 Op.\nO.L.C. at 38.\nMoreover, these operations furthered \xe2\x80\x9climited mission[s]\xe2\x80\x9d with welldefined and narrow objectives. Proposed Bosnia Deployment, 19 Op.\nO.L.C. at 332; see also, e.g., Military Force in Libya, 35 Op. O.L.C. at 38.\nIn the airstrikes directed at ISIL positions around Mount Sinjar and Erbil,\nPresident Obama directed U.S. military forces to conduct operations that\nwere \xe2\x80\x9climited in their scope and duration as necessary to protect American personnel in Iraq by stopping the current advance on Erbil by [ISIL]\nand to help forces in Iraq as they fight to break the siege of Mount Sinjar\nand protect the civilians trapped there.\xe2\x80\x9d August 8 Report to Congress; see\nalso, e.g., President Obama August 7 Statement (describing the operations\xe2\x80\x99 scope and purpose). The later operations against ISIL positions\naround the Mosul Dam, Amirli, and the Haditha Dam were similarly\nlimited to specific, narrowly defined objectives involving the protection\nof Americans, assistance to Iraq, and the prevention of humanitarian\ncatastrophe. See August 17 Report to Congress (indicating that the President had authorized \xe2\x80\x9ctargeted air strikes to support operations by Iraqi\nforces to recapture the Mosul Dam\xe2\x80\x9d); September 1 Report to Congress\n(stating that operations related to Amirli would be \xe2\x80\x9climited in their scope\nand duration as necessary to address this emerging humanitarian crisis and\nprotect the civilians trapped in\xe2\x80\x9d the town); September 8 Report to Congress (indicating the operations would \xe2\x80\x9cbe limited in their scope and\nduration as necessary to address th[e] threat [to Haditha Dam] and prevent\nendangerment of U.S. personnel and facilities and large numbers of Iraqi\ncivilians\xe2\x80\x9d). It was thus anticipated that the specific operations at issue\nwould be confined to narrow geographic regions within Iraq and would\nserve limited and largely \xe2\x80\x9cprotective purposes\xe2\x80\x9d that did \xe2\x80\x9cnot aim at the\nconquest or occupation of territory\xe2\x80\x9d or \xe2\x80\x9cat imposing through military\nmeans a change in the character of a political regime.\xe2\x80\x9d Proposed Bosnia\n121\n\n\x0c38 Op. O.L.C. 82 (2014)\n\nDeployment, 19 Op. O.L.C. at 332. Those factors made it less likely that\nthe operations would be of a lengthy duration or that, as a result of the\noperations, the United States would \xe2\x80\x9cfind itself involved in extensive or\nsustained hostilities.\xe2\x80\x9d Id.; see also 1994 Haiti Deployment, 18 Op. O.L.C.\nat 173 (anticipated military operations did not amount to a \xe2\x80\x9cwar\xe2\x80\x9d in part\nbecause they \xe2\x80\x9cdid not involve the risk of major or prolonged hostilities\xe2\x80\x9d).\nBecause of the absence of ground troops and the limited nature of the\nspecific missions involved, the anticipated operations discussed in this\nopinion did not, in our view, amount to a \xe2\x80\x9cprolonged and substantial\nmilitary engagement[] . . . involving exposure of U.S. military personnel\nto significant risk over a substantial period.\xe2\x80\x9d Military Force in Libya, 35\nOp. O.L.C. at 31. We therefore conclude that the \xe2\x80\x9canticipated nature,\nscope, and duration\xe2\x80\x9d of those military operations did not rise to the level\nof a \xe2\x80\x9cwar\xe2\x80\x9d within the meaning of the Declaration of War Clause.\nIII.\nFor the reasons set forth above, we conclude that President Obama had\nthe constitutional authority to order the targeted airstrike operations\nagainst ISIL described above. The President reasonably determined that\nthese military operations furthered important national interests in protecting American lives, assisting an ally or strategic partner at its request, and\npreventing humanitarian catastrophe; and the anticipated nature, scope,\nand duration of the operations were sufficiently limited so as not to require prior congressional approval.\nKARL R. THOMPSON\nPrincipal Deputy Assistant Attorney General\nOffice of Legal Counsel\n\n122\n\n\x0c'