Targeting Terrorist Leaders After Al-Baghdadi: Legal And Tactical Expectations

“For By Wise Counsel, Thou Shalt Make Thy War.”-Proverbs, 24 (6)

Under the protective tutelage of an American president, any American president, “We the People” should expect reasonable levels of safety in world politics.  At a minimum, we should be able to assume that  wide and predictably capable circles of public authority remain ready to thwart terrorist attacks. Most urgently, of course, such assurances should apply with special clarity to mega-terrorist attacks.


By definition, such mega or WMD aggressions would involve chemical, biological or nuclear elements.[1]

Here, there are both legal and operational issues to be considered. In terms of United States law, the authoritative roots of any such presumptive  assurances go back to Roman statesman Cicero (“The safety of the people shall be the highest law.”) and to seventeenth century English philosopher, Thomas Hobbes. [2] Though plainly unfamiliar to America’s current president, Hobbes’ Leviathan was central to the education of Thomas Jefferson and other Founders.

Notwithstanding far greater difficulties of literary access and convenience in the eighteenth century, the author of America’s Declaration was impressively well read. He cared, really cared, about serious and dignified learning. In stark contrast to Donald J. Trump’s current inversion of US policy-making priorities, which  center on one conspicuous sort or other of “branding,” Jefferson believed in the primacy of intellectual “preparation.”


For Jefferson, erudition maintained an intrinsically serious meaning. It was never something to be used or exploited solely for private embellishment or public adornment.

For the nation’s third president, diplomacy and strategic bargaining  were analytic responsibilities. Accordingly, they were always about variously disciplined calculations. They were never merely about shallow bluster or feigned “attitude.”

Looking ahead to continuously effective US counterterrorist preparations, America’s national security establishment must remain ready for absolutely all contingencies. This needed preparedness includes building the conceptual foundations for any future Abu Bakr al-Baghdadi or Osama Bin-Laden “elimination-type” operations.[3] During the Obama years, one major targeted killing of a Jihadist terrorist was the September 2011 US drone-assassination of Anwar al -Awlaki in Yemen.[4] That case was notably “special” in one frequently overlooked aspect: The Jihadist al-Awlaki was born in New Mexico, and was ipso facto a US citizen.

Despite the US Constitution’s Fifth Amendment protections concerning “due process,”[5] al-Awlaki’s targeted killing represented a tactical option that could sometime need to be repeated.

There are other pertinent concerns. Regardless of clearly valid issues concerning legal permissibility, it is by no means certain that targeting terrorist leaders will prove continuously useful to supporting US national security objectives. What this means, in brief, is that the virulence and capacity of any relevant anti-American or anti-Western ideology (especially a Jihadist-type ideology) might not be removed or even meaningfully blunted by designated terrorist assassinations.

It is even conceivable, in these more-or-less singular matters, that the net security effect of any such “removal” could be markedly negative rather than reassuringly “cost effective.”

As a timely example, the recent elimination of al-Baghdadi could quickly or eventually bring to power in ISIS an even more capable and violent terrorist adversary. What then? In such an unexpected eventuality, the killing of al-Baghdadi will have produced various short-term political benefits for US President Donald Trump, but only at a significantly unacceptable national security cost.[6]

 There is more. For the United States, corollary legal issues must never be ignored. In relevant jurisprudential terms, we must already inquire: What explicit legal guidelines should we Americans expect our leadership to follow? To respond properly (among several other related and also intersecting concerns), Mr. Trump and his counselors would then need to ask: “Is it sufficiently legal to target and kill recognizable terrorists if verifiable linkages between prospective targets and discernible attack intentions can be reliably documented?”  

To properly answer this fundamental or core question, it will first be necessary for Mr. Trump’s relevant national security officials to ask whether a proposed terrorist killing plan would be gainfully preemptive or just narrowly retributive. If the latter, a judgment wherein national self-defense was not in any way the genuinely underlying action-rationale, authoritative determinations of legality could become more and more problematic.[7]

On occasion, matters could get even more complicated. After all, assassination is explicitly prohibited by US law.[8]  It is also generally a crime under international law, which, though not widely understood,[9] remains a legitimate and integral part of American domestic law.[10] Still, at least in certain more-or-less residual circumstances, the targeted killing of Jihadist terrorist leaders could be correctly excluded from certain ordinarily prohibited behaviors. Here, such peremptorily protective actions could be defended as a fully permissible expression of  national law-enforcement.

A similar defense might sometimes be applied to the considered killing of terrorist “rank-and-file,” especially where such selective lethality had already become part of an ongoing pattern of US counter-terrorism. Earlier, the United States had widened the scope of permissible terrorist targeting in parts of Iraq, Afghanistan and Syria. In part, at least, such a widened operational arc of permissibility – one which now modifies the more stringent prior rules of engagement that had once required specific human target identifications – has been an inevitable byproduct of continuously developing technologies.

Most obvious among these emergent technologies is the growing US reliance upon drone-based assassinations, and also on other related forms of long-range or long-distance killing.

In the best of all possible worlds, there would be no need for any such decentralized or “vigilante” expressions of international justice.  But we don’t yet live in such an ideal world. Instead, enduring uneasily in our present and still-broadly anarchic legal order – a context that we international law professors usually prefer to call “Westphalian”[11] – the only real alternative to precise self-defense actions against terrorists is likely to be certain steadily worsening “in-theatre” instabilities.

Ultimately, such expanding hyper-instabilities could include more flagrant and consequential escalations of Jihadist terror-violence. Such escalations could be unaffected or encouraged by future US targeted killings. This is to be expected even where “retributive justice” appeared as both reasonable and legal.

At some indeterminable point, terror-violence escalations could lead to major or even unprecedented instances of chemical, biological or nuclear attack. Plausibly, these attacks might be undertaken by assorted sub-state adversaries or instead, by particular “hybrid” combinations of state and sub-state foes.

At the most basic level of any such issues and calculations, the very idea of assassination or targeted killing as remediation could seem paradoxical, almost an oxymoron.  Seemingly, at least, this understandably objectionable idea must preclude the input of all the more usual “due processes of  law” consideration. Yet, since the current or “Westphalian” state system’s original inception in the seventeenth century, international relations have never been governable by the same civil protections that are potentially available within democratic states.

In this persistently anarchic and prospectively chaotic world legal system, one which still lacks any duly-constituted and effective supra-national authority, assorted Jihadist leaders (ISIS, Hamas, Hezbollah, Islamic Jihad, al-Qaeda, etc) are already responsible for the mass killing of noncombatant men, women, and children of different nationalities. It follows, in at least some still-imaginable circumstances,  that where such leaders are not suitably “terminated” by the United States or by any of America’s key allies (e.g., Israel, in the tumultuous Middle East), incrementally egregious terror crimes could continue to multiply and also to remain unpunished.

Jurisprudentially, at least, any such predictable de facto impunity would be inconsistent with the universal legal obligation to punish international crimes, a jus cogens or peremptory obligation reaffirmed at the original 1945-46 Nuremberg Tribunal and subsequently in the 1946 and 1950 Nuremberg Principles.

 More formally, this lex talionis obligation, which comes to us from both ancient Roman law and the Hebrew Bible, is known correctly as Nullum crimen sine poena, or “No crime without a punishment.”[12]

Inevitably, complex considerations of law and tactics must inter-penetrate. In this particular connection, the glaring indiscriminacy of most jihadist operations is rarely if ever the result of enemy inadvertence. Rather, it is typically the intentional outcome of violent terrorist inclinations, unambiguously murderous ideals that lay deeply embedded in the Jihadist terrorist leader’s operative view of insurgency.

 For Jihadists, there can never be any meaningful distinction between civilians and non-civilians, between innocents and non-innocents. For these active or latent terrorist murderers, all that really matters are certain unassailably immutable distinctions distinguishing between Muslims, “apostates” and “unbelievers.”

As for the apostates and unbelievers, it is all quite simple.  Their lives, believe the Jihadists,  have literally no value. Prima facie, that is, they have no immunizing sanctity.  

In law, recalling Cicero, every government has both the right and the obligation to protect its citizens against external harms. In certain circumstances, this coincident right and obligation may extend derivatively to targeted killing. Actually, this point has long been understood (though also sometimes abused) in Washington, where every president in recent memory has given nodding or direct approval to “high value” assassination/targeted killing operations.

Certifiably, assassination is generally a tangible crime under international law. But in our essentially decentralized system of world law, self-help by individual states still remains altogether necessary, and is more-then-occasionally the only tangible alternative to suffering terrorist crimes. In the absence of particular targeted killings, terrorists could continue to create havoc against defenseless civilians almost anywhere, and do so with more-or-less complete impunity.

 A very specific difficulty here is this:  Jihadist terror criminals are usually immune to the more orthodox legal expectations of extradition and prosecution (Aut dedere, aut judicare).[13] This is not to suggest that the targeted assassination of terrorists will always “work” in tactical terms – indeed, there is literally nothing to support the logic of any such suggestion – but only that disallowing such targeted killing ex ante could not be operationally gainful or legally just.

In principle, if carried out with aptly due regard for pertinent “rules,” assassinating terrorist leaders could remain suitably consistent with the ancient legal principle of Nullum crimen sine poena, “No crime without a punishment.” Earlier, this original principle of justice had been cited as a dominant jurisprudential rationale for both the Tokyo and Nuremberg war crime tribunals. It was subsequently incorporated into customary international law, an authoritative legal source identified inter alia at Article 38 of the Statute of the International Court of Justice.[14]

 By both the codified and customary standards of contemporary international law, all terrorists are Hostes humani generis, or “Common enemies of humankind.”[15]  In the fashion of pirates, who were to be hanged by the first persons into whose hands they fell, terrorists are considered international outlaws who fall within the scope of “universal jurisdiction.” But choosing precisely which terrorists ought to be targeted remains a largely ideological rather than jurisprudential matter.

 Logically, in some current circumstances, tyrannicide could be seen as the “flip side” of American counter-terrorism. Historically, limited support for expressing assassination as a form of tyrannicide is not hard to discover.  It can be found, for example, in the classical philosophical writings of Aristotle and Plutarch as well as Cicero.

Overall, in his consideration of assassination or targeted-killing as counter-terrorism, President Donald Trump (or more realistically his designated counselors) should consider the clarifying position of Swiss scholar Emmerich de Vattel in his most famous work, The Law of Nations, or the Principles of Natural Law (1758): “The safest plan is to prevent evil where that is possible. A Nation has the right to resist the injury another seeks to inflict upon it, and to use force and every other just means of resistance against the aggressor.” 

Earlier, a similar view had been presented by Samuel Pufendorf in his seminal text, On the Duty of Man and Citizen According to Natural Law (1682): “Where it is quite clear that he is engaged in planning violence against me, even though he has not fully revealed his design, I shall be justified in immediately initiating self-defence by force, and in seizing the initiative against him, while he is still making preparations…..The aggressor will be taken to be the party which first conceived the intention to harm the other….To have the name of defender, it is not necessary to suffer the first blow, or merely to elude and repel the blows aimed at one.”

Even earlier, the right of self-defense by forestalling an attack had been established by the foundational Dutch scholar, Hugo Grotius, in Book II of The Law of War and Peace (1625). Recognizing the need for what later jurisprudence would reference as threatening international behavior that is “imminent in point of time” (See The Caroline Case, 1837), Grotius indicated that self-defense must be permitted not only after an attack has already been suffered, but also in advance, wherever “the deed may be anticipated.”

Further on, in the same chapter, Grotius summarized : “It be lawful to kill him who is preparing to kill.”

Interestingly, Vattel, Pufendorf and Grotius were all taken into primary account by Thomas Jefferson in his critical fashioning of the American Declaration of Independence.

There is more. In all these matters, one must assume rational calculation. If the expected costs of a considered assassination should appear lower than the expected costs of  alternative resorts to military force, assassination could emerge as the distinctly gainful and moral choice. However odious it might appear in isolation, assassination or targeted killing in certain circumstances could still represent a security-seeking state’s best overall option.

Assassination will always elicit indignation, even by those who could find large-scale warfare appropriate. But the civilizational promise of some more genuinely centralized worldwide security is far from being realized, and existentially imperiled states could sometime still need to confront critical choices between employing assassination in measurably limited circumstances or renouncing such tactics at the foreseeable expense of national survival. In facing such inherently difficult choices, these states will inevitably discover that all viable alternatives to the assassination option could also include large-scale violence, and these these alternatives are apt to exact a substantially larger toll in human life and suffering.

 Naturally, in a presumptively better world than this one, assassination could have no defensible place as counterterrorism, either as a preemptive measure or ex post facto, that is, as a permissible retribution. But, as if anyone should still need a reminder, we do not yet live in the best of all possible worlds, and the obviously negative aspects of  targeted killing should never be evaluated apart from the foreseeable costs of other still-available options. More precisely, such aspects should always be closely compared to what could reasonably be expected of plausible alternative choices.

International law is not a suicide pact. Ubi cessat remedium ordinarium, ibi decurritur ad extraordinarium;  “Where the ordinary remedy fails, recourse must be had to an extraordinary one.”

President Trump is correctly expected to comply with the rules and procedures of humanitarian international law; yet, he must also continue to bear in mind that Jihadist enemies will remain unaffected by these or any other jurisprudential expectations. Assassination and other still broader forms of preemption may sometimes be not only allowable under binding international law, but also indispensable. Conversely, there are occasions when strategies of assassination or targeted killing could be determinedly legal but remain operationally ineffectual.

Now, recalling the close connections between international law and US law – connections that extend to direct and literal forms of  legal “incorporation” – an American president can never choose to dismiss the law of war on grounds that it is “merely” international. Always, President Trump should consider aptly decipherable connections between assassination, counter-terrorism and United States Constitutional Law. Unexpectedly or not, the targeted killing of Anwar al-Awlaki had been approved by US President Barack Obama  and also by a secret committee of advisors allegedly based within the US Department of Justice.

Under US law, we are now bound to inquire, should an American president ever be authorized to order the extra-judicial killing of a United States citizen – even one deemed an “enemy combatant” – without any at least perfunctory reference to “due process of law?” On its face, any affirmative response to this necessary query would be difficult to defend under the US Constitution.

Of necessity, such presidential approval would need to be based upon a reasonably presumed high urgency of terror threat posed by the prospective victim. Any such “authorized” targeted killing of  US citizens would express a potentially irremediable tension between theoretically indissoluble individual citizen rights and the increasingly peremptory requirements of national public safety.

 Always, US policy on assassination or targeted killing will have to reflect a very delicate balance. Most important, in any such equilibrating calculation, will be the protection of civilian populations from Jihadist terror-inflicted harms. In those fearful circumstances where such harms would involve unconventional weapons of any sort – chemical, biological or nuclear – the legal propriety of targeting Jihadist terrorists could become patently obvious and also “beyond reasonable doubt.”

Nonetheless, such proper legal assessments ought never be undertaken apart from various corresponding operational expectations. This means, inter alia, that before any “extraordinary remedies” should be applied, those presumptive remedies should appear to be not only legal, but also tactically and strategically sound. In this connection, it would make elementary good sense to extrapolate from classical Prussian strategist’s Carl von Clausewitz’s enduring mantra in On War.

Assassination, like war, should always be “…a continuation of political relations by other means.”

More specifically, the targeted killing of terrorist leaders should always be assessed against a determinable and pre-existing “political object.”

In the absence of tangible  “congruence” in any such assessment, there could be no valid reason to proceed with a considered force-based operation. This is the case even where the contemplated targeting would be presumptively lawful and/or where it could expect to produce positive military outcomes.

In his Utopia, published in 1516, Thomas More offered a curious but clarifying juxtaposition of foreign policy stratagems and objectives. Although the Utopians are expected to be generous toward other states, they also offer (in Book II) tangible rewards for the assassination of enemy leaders. This is not because Thomas More wished in any way to appear barbarous, but because he was a fully realistic “utopian.” Sharing with St. Augustine (whose City of God had been the subject of More’s 1501 lectures) a fundamentally dark assessment of human political arrangements, he constructed a “lesser evil” philosophy that favored a distinctly pragmatic and still plausible kind of morality.

Inter alia, Sir Thomas More understood that the truly tragic element of politics is constituted of certain conscious choices of evil for the sake of a greater good. With regard to our ongoing scholarly investigation of US national security and counter-terrorism,, this suggests that assassination must always remain disagreeable in the “best of all possible worlds” (for example, the Leibnizian world satirized by Voltaire in Candide), but that it may also represent a necessary expedient in a world that must remain irremediably imperfect. In any event, these are matters that need to be treated in broadly intellectual and historical terms, and not as seat-of-the-pants decisions based on momentary presidential whim or embarrassingly empty witticisms.

[1] On the plausible consequences of a full-scale nuclear war, by this author, see: Louis René Beres, Apocalypse: Nuclear Catastrophe in World Politics (Chicago: University of Chicago Press, 1980); Louis René Beres, Mimicking Sisyphus: America’s Countervailing Nuclear Strategy (Lexington, Mass., Lexington Books, 1983); Louis René Beres, Reason and Realpolitik: U.S. Foreign Policy and World Order (Lexington, Mass., Lexington Books, 1984); Louis René Beres, Security or Armageddon: Israel’s Nuclear Strategy (Lexington, Mass., Lexington Books, 1986); and Louis René Beres, Surviving Amid Chaos: Israel’s Nuclear Strategy (Rowman & Littlefield, 2016; 2nd ed., 2018).

[2] Hobbes argued convincingly that the international state of nature is “less intolerable” than that same condition among individuals in nature because, in the latter, the “weakest has strength enough to kill the strongest.” Significantly, with the spread of nuclear weapons, this difference is disappearing. Interestingly, in the pre-nuclear age, jurist Samuel Pufendorf, like Hobbes, was persuaded that the state of nations “…lacks those inconveniences which are attendant upon a pure state of nature….” Similarly, Spinoza suggested that “…a commonwealth can guard itself against being subjugated by another, as a man in the state of nature cannot do.” (See: Louis René Beres, The Management of World Power: A Theoretical Analysis, University of Denver, Monograph Series in World Affairs, Vol. 10, No.3., 1972-73, p. 65.)

[3] See Louis René Beres, “The Killing of Osama Bin Laden,” Crimes of War, Crimes of War Project, August 2011,; Louis René Beres, “Assassinating Terrorist Leaders: A Matter of International Law,” OUP Blog, Oxford University Press, May 4, 2011; and Louis René Beres, “After Osama Bin Laden: Assassination, Terrorism, War, and International Law,” Case Western Reserve Journal of International Law, 44 Case W. Res, J. Int’l 93 (2011).

[4] Although “assassination” and “targeted killing” are often used interchangeably, there are meaningfully core distinctions to be made. Using the precise scholarly criteria offered by Amos Guiora, an assassination is always an expressly political killing that involves treachery or perfidy, and is not directed toward any suspected terrorist. A targeted killing, on the other hand, is a violent and person-specific expression of preemptive self-defense, and is always oriented to preventing some future act of terrorism. Always, inter alia, the targeted individual must be presumptively involved in the planning and execution of new terrorist assaults. See Amos. Guiora, Legitimate Target: A Criteria-Based Approach to Targeted Killing (New York, Oxford University Press, 2013).

[5] In the U.S. Constitution, Amendments IV, V, VI and VIII comprise a “Bill of Rights” for accused persons, and the phrase “due process of law” derives from Chapter 29 of Magna Carta (1215),  wherein the King promises that  “no free man (nullus liber homo) shall be taken or imprisoned or deprived of his freehold or his liberties or free customs, or outlawed or exiled, or in any manner destroyed, nor shall we come upon him or send against him,  except by a legal judgment of his peers or by the law of the land (per legem terrae).”  See Coke,  Institutes,  Part 2:  50-51,  1669;  cited by E.S. Corwin,  The Constitution and What It Means Today  (New York:  Atheneum,  1963): 217.

[6] In this connection, it was surely not in overall US security interests for the American president to comment publicly  about al-Baghdadi that he “died like a dog….whimpering….like a coward.” Such inflammatory language was gratuitous at best, and could plausibly even incentivize future anti-American terrorism from various ISIS-related groups. Moreover, the language must assuredly have been invented by Trump.

[7] Here we must recall that criminal responsibility of leaders under international law is not limited to direct personal action nor is it limited by official position.  On the principle of command responsibility, or respondeat superior, see:  In re Yamashita,  327 U.S. 1 (1945);  The High Command Case (The Trial of Wilhelm von Leeb),  12 Law Reports Of Trials Of War Criminals 1 (United Nations War Crimes Commission Comp., 1949);  see Parks, Command Responsibility For War Crimes,  62 MIL.L. REV. 1 (1973);  O’Brien, The Law Of War, Command Responsibility And Vietnam,  60 GEO. L.J.  605 (1972);   U.S. Dept Of The Army, Army Subject Schedule No. 27 – 1 (Geneva Conventions of 1949 and Hague Convention No. IV of 1907),  10 (1970).  The direct individual responsibility of leaders is also unambiguous in view of the London Agreement, which denies defendants the protection of the act of state defense.  See AGREEMENT FOR THE PROSECUTION AND PUNISHMENT OF THE MAJOR WAR CRIMINALS OF THE EUROPEAN AXIS,  Aug. 8, 1945,  59 Stat.  1544,  E.A.S.  No. 472,  82 U.N.T.S.  279,  art. 7.

[8] See Exec. Order No. 12333, 3 C.F.R. 200 (1988), reprinted in 50 U.S.C.  Sec. 401 (1988).

[9] The authoritative sources of international law are listed comprehensively (and can be most conveniently found) at art. 38 of the Statute of the International Court of Justice.

[10] In the words used by the U.S. Supreme Court in The Paquete Habana, “International law is part of our law, and must be ascertained by the courts of justice of appropriate jurisdiction, as often as questions of right depending upon it are duly presented for their determination.  For this purpose, where there is no treaty, and no controlling executive or legislative act or judicial decision, resort must be had to the customs and usages of civilized nations.”  See The Paquete Habana, 175 U.S. 677, 678-79 (1900).  See also:  The Lola,  175 U.S. 677 (1900);  Tel-Oren v. Libyan Arab Republic, 726 F. 2d 774,  781, 788 (D.C. Cir. 1984)(per curiam)(Edwards, J. concurring)(dismissing the action, but making several references to domestic jurisdiction over extraterritorial offenses), cert. denied,  470 U.S. 1003 (1985)(“concept of extraordinary judicial jurisdiction over acts in violation of significant international standards…embodied in the principle of `universal violations of international law.'”).

[11] After the seventeenth century (1648) Peace of Westphalia, which ended the Thirty Years’ War and created the present conflictual system of independent states. See: Treaty of Peace of Munster, Oct. 1648, 1 Consol. T.S. 271; Treaty of Peace of Osnabruck, Oct. 1648, 1, Consol. T.S. 119. Together, these two agreements comprise the Peace of Westphalia. Thomas Hobbes’ Leviathan was first published in 1651, just three years after the Peace of Westphalia. It is at Chapter XIII that Hobbes famously references the “state of nature” as an anarchic situation characterized by “continuall feare; and danger of violent death….”

[12] Nullum crimen sine poena is the principle that distinguishes between criminal and civil law.  Without punishment there can be no distinction between a penal statute and any other statute. (See Redding v. State,  85 N.W. 2d  647, 652; Neb. 1957)(concluding that a criminal statute without a penalty clause is of no force and effect).  The earliest statements of Nullum crimen sine poena can be found in the Code of Hammurabi (c. 1728-1686 B.C.); the Laws of Eshnunna (c. 2000 B.C.);  the even-earlier Code of Ur-Nammu (c. 2100 B.C.) and of course the Lex Talionis or law of exact retaliation presented in three separate passages of the Jewish Torah or biblical Pentateuch.  At Nuremberg, the words used by the Court,  “So far from it being unjust to punish him, it would be unjust if his wrong were allowed to go unpunished,”  represented an unambiguous reaffirmation of Nullum crimen sine poena.  For the Court statement, see:  A.P. d’Entreves,  NATURAL LAW (London: Hutchinson University Library, 1964), p. 110. 

[13] The extradite or prosecute formula of international criminal law is deducible from Nullum crimen sine poena.  Existing since antiquity, it is an expectation with roots in both natural law (especially Jean Bodin, Hugo Grotius, and Emmerich de Vattel) and in positive law. See also: Resolution on Principles of International Cooperation in the Detection, Arrest, Extradition and Punishment of Persons Guilty of War Crimes and Crimes Against Humanity,  G.A. Res. 3074,  28 U.N.  GAOR,  Supp. No.30 at 78, U.N. Doc. A/9030, 1973;  G.A. Res. 2840,  26 U.N. GAOR Supp. No. 29 at 88,  U.N. Doc. A/8429,  1971;  G.A. Res. 96,  U.N. Doc. A/64 at 188, 1946;  Convention on the Non-Applicability of Statutory Limitations to War Crimes and Crimes Against Humanity,  adopted and opened for signature, ratification and accession by General Assembly Resolution 2391 (XXIII) of 26 November 1968,  entered into force,  11 November 1970.

[14] Article 38(1)(b) of the Statute of the International Court of Justice describes international custom as “evidence of a general practice accepted as law.”  59 Stat.  1031,  T.S. No. 993 (June 26, 1945).  Norms of customary international law bind all states irrespective of whether a State has ratified the pertinent codifying instrument or convention.  International law compartmentalizes apparently identical rights and obligations arising both out of customary law and treaty law.  “Even if two norms belonging to two sources of international law appear identical in content, and even if the states in question are bound by these rules both on the level of treaty-law and on that of customary international law, these norms retain a separate existence.”  See Military and Paramilitary Activities (Nicaragua v. U.S.),  1986 I.C.J. Rep.  14,  para. 178 (June 27).

[15] .On the concept of “common enemy of mankind,”  see:  Robert Alfert Jr.,  “Hostes Humani Generis:  An Expanded Notion of U.S. Counterterrorist Legislation,”  EMORY INTERNATIONAL LAW REVIEW,  Vol. 6,  No. 1,  Spring 1992,  pp. 171-214.

Prof. Louis René Beres
Prof. Louis René Beres
LOUIS RENÉ BERES (Ph.D., Princeton, 1971) is Emeritus Professor of International Law at Purdue. His twelfth and most recent book is Surviving Amid Chaos: Israel's Nuclear Strategy (2016) (2nd ed., 2018) Some of his principal strategic writings have appeared in Harvard National Security Journal (Harvard Law School); International Security (Harvard University); Yale Global Online (Yale University); Oxford University Press (Oxford University); Oxford Yearbook of International Law (Oxford University Press); Parameters: Journal of the US Army War College (Pentagon); Special Warfare (Pentagon); Modern War Institute (Pentagon); The War Room (Pentagon); World Politics (Princeton); INSS (The Institute for National Security Studies)(Tel Aviv); Israel Defense (Tel Aviv); BESA Perspectives (Israel); International Journal of Intelligence and Counterintelligence; The Atlantic; The New York Times and the Bulletin of the Atomic Scientists.