VII. ASYMMETRIC SELF-DEFENSE
The fiduciary character of sovereignty also offers insights for nontraditional battlefields such as transnational counterterrorism operations. Just as states bear obligations to respect human rights when they use force to quell domestic insurgencies, the fiduciary theory suggests that they must also observe IHRL constraints on the use of force when they use force against nonstate actors abroad with, or without, the host state's consent.
A. Jus ad Bellum
Questions regarding the application of IHL and IHRL to asymmetric self-defense have become increasingly important since the 9/11 terrorist attacks, as the United States and its allies have waged a global campaign to disrupt and dismantle the al- Qaeda terrorist network and other extremist groups that pose security threats. After invading Afghanistan in 2001, the United States soon broadened its counterterrorism operations to other states where al-Qaeda cells were believed to be operating. In December 2001, U.S.-led forces pursued Taliban insurgents beyond the borders of Afghanistan into the mountainous tribal regions of neighboring Pakistan. Subsequent operations targeted al-Qaeda-affiliated groups in Somalia and Yemen. Although it appears that the United States generally obtained other states' consent before using force within their territory, it did not follow this course in every case. Most prominently, in May 2011, U.S. special forces raided a compound in Abbottabad, Pakistan, killing al-Qaeda leader Osama Bin Laden without Pakistan's prior consent. Four months later, the United States conducted a drone and jet strike in Yemen to kill radical Islamic cleric Anwar Al-Awlaki, a U.S. citizen who had
Concluding Observations, ^ 11, U.N. Doc. CCPR/CO/78/ISR (Aug. 21, 2003), http://www. unhchr.ch/tbs/doc.nsf/(Symbol)/CCPR.CO.78.ISR.En?OpenDocument (last visited Nov. 25, 2015); Christian Tomuschat, Human Rights and International Humanitarian Law, 21 Eur. J. Int’l L. 15, 20 (2010).
allegedly participated in preparations for terrorist attacks against the United States. In August 2014, the united States joined NATo allies and other regional partners in targeting members of the so-called Islamic State of Iraq and the Levant (Islamic State), an extremist insurgent force that seeks to carve out a radical Islamic caliphate in the middle east. At the time of this writing, there is no end in sight to these targeted killing programs.
Although the 9/11 terrorist attacks and their aftermath have cast a fresh spotlight on the application of jus ad bellum principles to military operations against nonstate actors, the problem of asymmetrical self-defense is not new. Indeed, the classic nineteenth-century statement on preemptive self-defense, articulated by u.S. Secretary of State Daniel Webster during the Caroline affair of 1837, was prepared in response to the British government's use of force against nonstate actors in the united States. Concerned that an American ship was smuggling weapons across the Niagara River to Canadian rebels, British authorities had entered u.S. waters without the consent of the American government to neutralize the ongoing threat. Despite contesting the legality of this action, Webster agreed in principle that international law would permit cross-border military action where there was "a necessity of self-defence, instant, overwhelming, leaving no choice of means, and no moment for deliberation.” Under this influential Caroline doctrine, a vulnerable state's responsibility to protect its people, coupled with the absence of effective action from the host state, was understood to justify the use of force across international borders.
In the Charter era, it is far less clear whether states may use force in response to cross-border attacks by nonstate actors. Some authorities, principally in continental Europe, have concluded that only states are capable of conducting "armed attacks” within the meaning of Article 51, so the violent acts of nonstate actors can never trigger a right to self-defense under the Charter. Although the ICJ has adopted a more nuanced approach to the issue, it too has held that Article 51 requires state action to justify the use of force in self-defense. According to the ICJ, attacks by nonstate actors must be "imputable to a foreign State” based on a foreign state's effective control in order to trigger the right of self-defense under international law. Moreover, even if nonstate actors are subject to a host state's effective control, the ICJ has reasoned that low-level violence, such as episodic rocket attacks or suicide bombings, does not meet the test of severity that distinguishes an “armed attack” from lesser violence under the Charter. Thus, the ICJ has erected formidable hurdles to states' use of force against nonstate actors beyond their borders— hurdles that would preclude military action in contexts such as the Caroline affair and the Bin Laden operation.
Although the text of the Charter does not rule out the ICJ's approach to asymmetric self-defense, its reading of Article 51 is not compelled by the text itself, and it has encountered stiff resistance in recent years from a growing number of states. In the 1970s and 1980s, the international community reacted with skepticism, if not outright hostility and condemnation, when states invoked Article 51 as a basis for cross-border military action in response to attacks by nonstate actors. Beginning in the 1990s, however, a diverse collection of states have asserted the right to use force to defend their people against attacks from terrorist cells, paramilitary groups, and private militias outside their borders. In the immediate aftermath of the 9/11 terrorist attacks, the Security Council appeared to take sides in this debate by describing these attacks as “a threat to international peace and security” that had triggered “the inherent right of individual or collective self-defence in accordance with the Charter.” More recently, the multinational coalition of states that is attempting to neutralize the Islamic State in Syria has relied on arguments based on individual or collective self-defense under Article 51—notwithstanding the fact that most have not sought Syria's approval for military intervention. Although the ICJ has generally resisted these trends, many governments and legal scholars now embrace the idea that states may use force in self-defense against dangerous nonstate actors outside their own borders without either Security Council authorization or the host state's consent, if the host state allows its territory to be used as an operational command center or staging ground for cross-border attacks.
At present, it is unclear how this debate over the legality of asymmetrical selfdefense will be resolved. Should the ICJ's interpretation of Article 51 prevail, states could claim authority under international law to use force abroad without Security Council authorization or the other state's consent only if the armed attacks were conducted by a foreign state or by nonstate actors under the foreign state's control. under this approach, states could continue to use force against nonstate actors within their own borders, consistent with IHRL, where absolutely necessary to protect their people. But they would have to seek the Security Council's approval for any cross-border military response to attacks committed by nonstate actors operating outside another state's control. The Security Council would therefore be solely responsible for deciding whether responsive military action would further the international legal system's overarching fiduciary purpose to establish a regime of secure and equal freedom.
If the ICJ's interpretation of Article 51 does not ultimately prevail, states could assert broader authority under international law to use force outside their borders without the Security Council's ex ante authorization. even in this scenario, however, well-established principles of international law dictate that lawful cross-border military action would be exceptionally rare, and it would always be subject to scrutiny by the international community ex post. For example, the Charter provides that a threat to national security must cross the "armed attack” threshold to support selfdefense. Sporadic incidents of low-intensity violence by nonstate actors do not suffice under this standard. Customary principles of jus ad bellum such as necessity, imminence, and proportionality likewise limit the use of force abroad. Additionally, states may not use force against nonstate actors abroad if attacks can be averted through diplomacy, peaceful dispute-resolution mechanisms, non-forcible countermeasures such as economic sanctions, or appeals to either the Security Council or the host state. Even ifthese requirements are satisfied, the fiduciary theory suggests that states as fiduciaries of humanity must refrain from using force against nonstate actors abroad if such action could foreseeably trigger an international armed conflict with the host state that would pose a disproportionate threat to international peace and security. Thus, even if the ICJ eventually defers to countercurrents in state practice, states will rarely be justified in using force against nonstate actors abroad without the consent of either the Security Council or the host state, and when they purport to have an adequate justification for the use of force, they must still render an account ex post to the international community, taking into consideration the principles sketched above that limit the extraterritorial use of force.
-  See Joint Statement Issued by Partners at the Counter-ISIL Coalition Ministerial Meeting,Dec. 3, 2014, http://www.state.gov/r/pa/prs/ps/2014/12/234627.htm; Alissa J. Rubin et al.,U.S. Jets and Drones Attack Militants in Iraq, Hoping to Stop Advance, N.Y. Times, Aug. 8, 2014,http://www.nytimes.com/2014/08/09/world/middleeast/iraq.html?_r=0.
-  Webster to Fox, 24 Apr. 1841, 29 BFSP at 1137-38, http://avalon.law.yale.edu/19th_cen-tury/br-1842d.asp.
-  See, e.g., Antonio Cassese, The International Community's “Legal” Response to Terrorism, 38Int'l & Comp. L.Q. 589, 597 (1989).
-  See Legal Consequences of the Construction on a Wall in the Occupied PalestinianTerritory, Advisory Opinion, 2004 ICJ Rep. 136 (July 9) (Palestinian Wall); Case ConcerningArmed Activities on the Territory of the Congo (Congo v. Uganda), 2005 ICJ Rep. 168, 223(Dec. 19) (Armed Activities).
-  See Armed Activities, 2005 ICJ Rep. 201, ^ 147; Palestinian Wall, 2004 ICJ Rep. 207, ^ 139.
-  See Case Concerning military and Paramilitary Activities in and Against Nicaragua (Nicaragua v. United States), 1986 ICJ Rep. 14 (June 27), 191, 210-11, 247-49; Case Concerning Oil Platforms (Islamic Republic of Iran v. United States of America), 1986 ICJRep. 803 (Nov. 12), 51-64 (Oil Platforms); cf. Eritrea-Ethiopia Claims Commission, Partial Award, Jus ad Bellum, 19 Dec. 2005, ^ 12.
-  See Palestinian Wall, 2004 ICJ Rep. 207, ^ 3 (July 9) (Higgins, J., separate opinion) (“Thereis, with respect, nothing in the text of Article 51 that thus stipulates that self defense is availableonly when an armed attack is made by a State . . . .”).
-  See Christian Tams, The Use of Force Against Terrorists, 20 Eur. J. Int'l L. 359, 367-68(2009) (discussing criticism of “self-defence” operations undertaken by Israel, South Africa, andthe United States).
-  See Theresa Rheingold, State Weakness, Irregular Warfare, and the Right to Self-Defense Post9/11, 105 Am. J. Int'l L. 244, 285 (2011) (collecting examples); Tams, supra note 104 (same).
-  U.N. Sec. Council Res. 1368, SC/Res/1368 (Sept. 12, 2001).
-  See, e.g., Letter from U.S. Special Representative to the United Nations Samantha J. Powerto U.N. Secretary-General Ban Ki-moon, Sept. 23, 2014.
-  Some judges of the ICJ, however, have concluded that attacks by nonstate actors may trigger a right to self-defense. See Case Concerning Armed Activities on the Territory of the Congo(Congo v. Uganda), 2005 ICJ Rep. 168 (Dec. 19) (separate opinions of Judges Simma andKoojimans); Palestinian Wall, 2004 ICJ Rep. 207, ^ 6.
-  See, e.g., Daniel Bethlehem, Self-Defense Against an Imminent or Actual Armed Attack byNonstate Actors, 106 Am. J. Int'l L. 770, 774-77 (2012). Some authorities characterize the applicable legal standard for bypassing the host state's consent as an “unable or unwilling” test; othersas an “aiding and abetting” requirement. Compare Elizabeth Wilmhurst, Chatham HousePrinciples on Self-Defense 11-13 (Oct. 2005) (unable or unwilling), and Ashley Deeks,"Unwilling or Unable": Toward a Normative Framework for Extraterritorial Self-Defense, 52 Va.J. Int'l L. 483 (2012) (unable and unwilling), with Tams, supra note 104, at 385-86 (aiding andabetting); and Tom Ruys & Sten Verhoeven, Attacks by Private Actors and the Right of Self-Defense,10 J. Conflict & Sec. L. 289, 312-17 (2005) (aiding and abetting). A few commentators havetaken the more aggressive position that states may use force abroad in response to terroristattacks irrespective of whether the host state is willing and able to neutralize the threat. See, e.g.,JuttA Brunnee & Stephen Toope, Legitimacy and Legality in International Law296 (2010); Raphael Van Steenberghe, Self-Defence in Response to Attacks by Non-state Actors inthe Light of Recent State Practice: A Step Forward?, 23 Leiden J. Int'l L. 183, 184 (2010).
-  See, e.g., Armed Activities, 2005 ICJ Rep. 168, at 223; Case Concerning Military andParamilitary Activities in and Against Nicaragua (Nicaragua v. United States), 1986 ICJ Rep. 14,at 101-03.
-  See Report of the Secretary-General's High-Level Panel on Threats,Challenges and Change, A More Secure World: Our Shared Responsibility (2004).
-  As with any other exercise of individual or collective self-defense, a state's use of forceagainst nonstate actors abroad is subject to ex post scrutiny by the broader international community to assess compliance with jus ad bellum. Although there is currently no formal institutional mechanism in place for international review of state decisions to use force (aside from theInternational Criminal Court's limited jurisdiction over the crime of aggression), internationalreview may take the form of U.N. Security Council or General Assembly resolutions, investigations by independent international commissions, or decentralized responses by states andregional organizations.