It is necessary to venture into the jus ad bellum issue of self-defense (or UNSC authorization) if the state concerned wishes to use force outside its territory, as this is the only way of justifying what would otherwise be a violation of another state’s sovereignty. Let’s assume that the US legal argument that it is in a state of armed conflict with Al Qaeda is correct; imagine that Osama bin Laden is located somewhere in Germany. The US can’t just send a Predator drone after him; it either needs Germany’s consent, or it needs to prove that it has the right to use force under the jus ad bellum (e.g. that it is doing so to prevent an imminent armed attack). If these conditions are not met, the drone attack could be lawful under IHL and IHRL, but unlawful under the jus ad bellum.

You say that whether an exercise of self-defence is lawful will depend on whether the relevant rules of IHL or IHRL are complied with. It is my understanding that in the context of an armed conflict, IHL and IHRL will apply, the latter to the extent that it is not inconsistent with IHL. My question therefore is why would a state even be invoking self-defence as a matter of jus ad bellum if they were in an armed conflict? Wouldn’t the invocation of self-defence as an exception to the prohibition on the use of inter-state force only be relevant outside of an armed conflict?

Nobody here has argued that human rights norms preserved by BOTH IHL and IHRL do not apply in armed conflict or are subject to a necessity override. Further, nobody has argued that jus cogens norms, such as the prohibitions of genocide or torture, do not apply in armed conflict or are subject to a necessity override. Your comments in this area are unnecessary.

As my earlier posts should have made clear, I do not argue that the IHL entirely precludes the application of IHRL. However, it would seem to preclude the application of it as between enemy combatants, at a minimum, and with regard to other IHRL norms that are inconsistent with conduct permitted by IHL, such as a proportionate attack. This would also seem to be state practice.

To say that some human rights norms are generally nonderogable jus cogens or that some are nonderogable in war is NOT to say that NONE are nonderogable. War permits the destruction of life and property otherwise abhorrent to civilized society. Some norms applicable in peace are simply not applicable in war.

As was implicit in my earlier posts, the deprivation of the fundamental right to life of enemy belligerents/combatants/fighters is a common feature of war. Outside of the context of an armed conflict, widespread and systemic mass murder of individuals is a crime against humanity. Within armed conflict, it is permitted between enemy combatants not hors de combat. Thus, I do not understand your comment that “I know of no relevant human right that would needlessly inhibit lawful conduct on the battlefield”.

When the U.S. engages in a drone attack, the context of my earlier comments, it believes the target to be an enemy combatant/fighter in armed conflict. IHL provides protections to the individuals targeted. For example, they cannot be subjected to unnecessary suffering, to the use of poison, or perfidiously attacked, etc. The application of ALL IHRL to the targeted individual combatant in this context is problematic.

Marko has argued applying IHRL is proper (for various reasons) and requires that there be a demonstrable, imperative necessity to the attack against them. I do not believe that view to be consistent with common understandings of armed conflict and IHL with regard to either international or non-international armed conflict.

The real challenge is in understanding the geographic applicability of IHL, particularly in non-international armed conflict. This is what many scholars argue, that IHL does not apply in Pakistan or Somalia or anyplace not at the (internal) armed conflict threshold. At least as to attacks on combatants and civilians taking a direct part in hostilities, as well as to proportionate civilian deaths incident to those attacks, I disagree with that view. However, detention and prosecution of civilians not taking a direct part in hostilities is different. One must understand the history of the development of civilian protections in war to understand why this is the case.

I admit that my comments were more broadly directed not only to your main post, but also to the string of comments. Regarding self defense against a non-state actor, I agree that the concept does not preclude the wrongfulness of the violation of a terrorist group’s host state’s territorial integrity. I do feel that necessity and/or responsibility coupled with a countermeasure might, as those concepts are discussed in the Draft Responsibility of States for Internationally Wrongful Acts. I mentioned this in earlier discussions here.

(1) Regarding your comment that the “practice of states in interpreting a treaty is of course a relevant consideration in treaty interpretation, but one most certainly does NOT need to establish state practice and opinio juris in order to reach a conclusion on treaty interpretation.” My point is that state practice is necessarily relevant to understanding the relationship between both conventional and customary IHL and IHRL, and that we academics (and courts) too often make legalistic arguments without regard to it. The range of potentially applicable treaties and customs here are quite broad. See also comment (4) below.

(2) Regarding your statement that “lex specialis…is precisely an academic or judicial construct,” this is to my mind mistaken. Commentators have long mentioned a concept of lex specialis with regard to IHL. Writing in 1863, Halleck stated that ONLY IHL governs the “belligerent intercourse” of opposing forces in an armed conflict. Lieber said the civil law is suspended between armed forces in the field.

These commentators were attempting to theoretically describe state practice with regard to war, both international and non-international/civil. One must never forget that modern IHL consists of customary and conventional CONSTRAINTS on armed conflict that were once almost fully, as a legal matter, unrestrained. Given this fact, it is the extent to which states understand customary and/or conventional IHRL to further constrain their conduct in either international or non-international armed conflict that matters. That relationship is rarely clear based solely on the text of treaties, perhaps other than the ECHR in some circumstances, making state practice and opinio juris quite important outside of Europe.

(3) I further disagree that the jus in bello is irrelevant to self defense. Should a state resort to armed force in response to an armed attack, the jus ad bellum regulates the resort to force, and the jus in bello of IHL governs use of force in the resulting armed conflict. I do not think there is any question regarding this in a Common Article 2 international armed conflict, nor should we doubt it in principle when discussing “armed conflict not of an international character.”

The question in the first instance is whether IHL applies at all. When there is an armed conflict, it does, and it regulates all hostilities and attacks. The conflict begins with the first armed attack. A full scale invasion is not required to sustain or establish it. You question whether IHL’s targeting rules “displace IHRL” (again, this would be a matter of state practice unless expressly covered in an applicable treaty) and I don’t in principle (but particulars are sticky).

What IHL purposefully permits and prohibits makes no sense with IHRL superimposed on it. It is theoretically problematic to say that because an armed conflict does not yet exist in the area of the counter-attack, IHL does not apply. By that logic, it would seem that the state that initiates or responds to even an international armed attack within an armed but, for-the-moment peaceful geographic region always violates IHRL until the armed conflict threshold is reached and sustained. If IHRL necessarily applies concurrently with IHL, Art. 75 of the first Geneva protocol and Art. 6 of the second are largely superfluous.

(4) I again caution that whatever the ECtHR says about the relationship of the ECHR to IHL in places where the ECHR applies, the U.S. is not a party to the ECHR and neither is Pakistan (nor any other state where drone attacks are taking place). We are therefore talking about other IHRL conventions or customary laws that are of less certain relevance. When you resort to the ECHR for a rule (as you did in your main post and your comment above) when discussing the U.S. and other states not party to it, you necessarily imply that its rule applies as or reflects custom. It is not solely a matter of treaty interpretation, as you claim, unless a state is party to the ECHR and the ECHR clearly applies under the circumstances.

By way of example, you cite Art. 2 of the ECHR immediately above for a certain principle, but it does not necessarily reflect the historical view of the U.S. (though admittedly that view is not entirely clear) or non-European countries. At what point does a riot or insurrection become internal “armed conflict” under the ECHR? What is the legal consequence or effect of that with regard to the application of IHL?

It is possible to view the second Geneva protocol triggering provisions as establishing the threshold at which IHL displaces IHRL in internal armed conflict (for non ECHR members). It is also possible to view it as the point at which the rules it contains merely supplement those in Common Article 3 and any otherwise applicable customary law (as a matter of conventional law for its states party) or as reflecting additional customs that apply at that threshold to states not party. Each state might view it differently. The ECHR may or may not reflect universal custom on the point. At any rate, I repeat that Art. 6 and most other provisions would be a largely superfluous supplement to IHRL if one believes it necessarily applies.