Mike Lewis Is Wrong About the Nature of Self-Defence

by Kevin Jon Heller

Mike Lewis has a guest post at Just Security today responding to Ryan Goodman’s recent post exploring what the US’s claimed “unwilling or unable” test for self-defence against non-state actors means in the context of Syria and ISIS. Ryan, careful scholar as always, rightly points out that the test “remains controversial under international law.” Mike doesn’t seem to have any such qualms, but that’s not what I want to respond to here. Instead, it’s important to note that Mike makes a basic error concerning how the “unwilling or unable” test functions — assuming for sake of argument it is a valid approach to self-defence under Art. 51 of the UN Charter (emphasis mine):

It is important to note that this interpretation does not give the US unlimited license to act in violation of the sovereignty of other states as some opponents of the standard claim. There are limits and dangers associated with taking such a course of action. First of all, an intervening state can only take such actions after giving the host/target state a meaningful opportunity to prevent its territory from being used by the non-state actor to launch attacks. In the case of Syria, there is no question that it is unable to control the territory under ISIS control so further delays are unnecessary. Secondly, the intervening state does so at its own peril. Syria can rightfully interpret any strikes as aggression by the US and it is justified in taking steps to prevent such attacks and to destroy the drones/aircraft conducting such attacks.

Um, no. The entire point of arguing self-defence — in any form, including pursuant to the controversial “unwilling or unable” test — is that it cures any violation of state sovereignty under Art. 2(4) of the UN Charter. So if the US attacked ISIS in Syria because Syria was unwilling or unable to prevent ISIS from using its territory as a base for attacks, the US would not violate Art. 2(4) and Syria would have no right whatsoever to act in self-defence against that armed attack. Indeed, any attempt to “prevent such attacks and to destroy the drones/aircraft conducting such attacks” would represent an act of aggression by Syria against the US, thereby opening the door to legitimate acts of self-defence against Syria itself.

Again, I don’t accept that the “unwilling or unable” test reflects current customary international law. But it’s important not to let that debate obscure how self-defence functions under Art. 51 of the UN Charter.


25 Responses

  1. Wow! Kevin: you are entirely correct with respect to your conclusions about use of force under 2(4) and 51. In the actual context, use of force against ISIS in Syria at this point would not involve U.S. measures of “self-defense” however. The claim should be that the U.S. is engaging in measures of collective self-defense within Art. 51 with the consent of Iraq and, because is under a process of armed attacks from the nonstate actor ISIS, that these measures of collective self-defense can also occur in Syria against ISIS whether or not the Assad regime is “unwilling” (surely not) or “unable” (apparently yes).
    I agree that “unwilling or unable” is not a limitation of the inherent right of self- or collective self-defense if an armed attack is underway, but armed attacks emanating from the territory of another state, for that period of time, do fit within a conclusion that that state is “unable.”

  2. p.s. I note that you must, therefore, agree with the majority of textwriters on these points and disagree, for example, with Mary Ellen.

  3. I completely agree with you regarding the effect of the unable or unwilling test, Kevin.

    I also note that a Syrian counter-attack would then, under the appropriately low threshold established by Common Article 2 of the 1949 Geneva Conventions, create an international armed conflict between Syria and the U.S. Could the President then claim independent Article II authority to respond? To what extent? Inquiring minds wonder whether or the extent to which the administration has considered this question.

  4. John,

    Excellent question. I assume the President would then have the authority to prosecute the conflict, given that you’re absolutely right a Syrian response would trigger IAC. As for War Powers questions, that’s well above my pay grade…

  5. Well, I wonder whether proportionality requires what Dinstien would call defensive armed reprisals or whether a entire defensive war could be justified. That would be an interesting back door into the Syrian conflict. Thinking about that potential result in advance might prevent Syria from attempting to respond other than through diplomatic protests.

  6. Kevin, I agree with you that if any intervening state truly acts in self-defense, then the state where the intervention is taking place cannot argue that the intervening nation acted aggressively. However, it is worth pointing out that just because a state says it is acting in self-defense, it does not mean that it is rightfully acting in self-defense. Many states have argued self-defense for actions that could be easily perceived as aggression. I would thus disagree that any time a state “argues” it is acting in self-defense, this “cures” the sovereignty violation under article 2(4). If Syria launched air strikes against Iraq, for example, and if it claimed that it was doing so in self-defense (because of the ISIS threat emanating from Iraq), would be immediately accept the self-defense argument or would we instead debate that this was aggression?

  7. John: if Syria attacked, the response must be “proportionate” — so it would depend on to what extent Syria attacked. Yes, of course, an IAC (like the 30 min. “war” over Libya as U.S. “self-defense” in 1986).

  8. Milena,

    I certainly didn’t mean to imply that merely arguing self-defence cures the violation of sovereignty — or that states themselves decide when an act qualifies as self-defence. I simply meant that the reason states argue self-defence is that, if the claim is valid, the territorial state cannot complain about the violation of its sovereignty.

  9. Thanks for the post. the respectable author of that post , has clearly ignored the composition words of : ” territorial integrity ” in Article 2 ( 4 ) . Means, where such integrity has been dismantled or impaired , due to such or such circumstances, then, apparently, there is an enhanced right of an invader or ” striker ” , to rush for his own self defense , let alone , while the cause of self defence , has to do or is clearly related to such disintegrity ( like apparently the case in Syria ) .


  10. Assuming “unwilling or unable” is a standard seems to be very problematic and dangerous as it is a huge condition precedent for the discussion.

    Both Syria and the US would assert their responses were self-defense – probably with joyous ISIS in Syria and Iraq happy to be exploiting geopolitical fault lines.

    What if after the American assertion of self-defense going in after ISIS, Syria says that the American self-defense is not proportionate and amounts to aggressive war for which Syria asserts self-defense and Russia asserts collective self-defense on the side of Syria? Where are we then?

  11. Rudyard Kipling in 1899 and local angle press proportionality merit our attention in this terribly dangerous time. Just updated over at saltlaw.org/blog to bring up the risk of tu quoque defenses being asserted.

    Nothing new under the sun.


  12. Thanks for pointing this out Kevin and for the subsequent posts.
    Just a small (though important) precision from an IHL perspective: an IAC could triggered as soon as the US strike ISIS in Syria, if the strikes are conducted without Syria’s consent. A response by Syria is not necessary to trigger IHL applicability (a response by the attacked State has never been a condition for the existence of an IAC under IHL!). The Syrian government issuing a statement opposing the US strikes and the violation of its airspace, would be sufficient to classify the situation between the US and Syria as an IAC. Then of course, the unsettled question what if Syria remains silent? My guess is that, even though Syria does not publicly oppose the strikes, but it retaliates later, that would be an evidence of the absence of consent, and therefore, IHL could be applied retrospectively to the first US strike.

  13. Thanks Benjamin, I missed that piece of info.
    Then, from an IHL point of view, the situation in my humble opinion is pretty clear: as soon as the US will use force in the territory of Syria, even if it targets ISIS positions (and not the Syrian military), it will be engaged in an IAC against Syria (with all of what this implies in terms of applicability of the rules on the conduct of hostilities – including US military personnel becoming legitimate targets – and US and Syrian citizens becoming ‘protected persons’).
    That is independent from the classification of the relationship US/ISIS, which may constitute a parallel NIAC. If we reject the view that ISIS can be assimilated to Al-Qaeda or its associated forces (which is indeed too far a stretch of the law, as usefully reminded by several commentators in this blog and elsewhere since yesterday), then the US could still be engaged in a NIAC against ISIS alone; provided the organisation criterion is fulfilled (at this stage I doubt one can have a firm assessment on this one given the lack of information on ISIS’s internal command structure), and provided that the threshold of intensity is met (which we shall see in the coming days will tell…).

  14. Nina: the U.S. is presently engaged in an IAC in Iraq with the consent of the Iraqi govt. and the use of force in legitimate collective self-defense against ISIS in Syria would not be an armed attack on Syria or trigger and IAC with Syria. Iraq had been in a NIAC with ISIS prior to U.S. intervention, but that intervention shifted to conflict to an IAC (and apparently other countries are directly involved as well).

  15. Hello Jordan,
    my answer was based on the widely accepted view according to which the qualification of an armed conflict under IHL depends on the nature of the parties involved, and not on territorial elements. In order to have an IAC you need to have two or more State entities fighting (cf the wording of Art. 2 common to the GCs, extensive practice and literature), that makes absolutely no doubt.
    I would be curious to know under what basis you think the US is engaged in an IAC currently in Iraq? By definition, if the territorial State consent to the use of force by a foreign State, there can be no IAC between those two States. There can however, be a NIAC against the US and ISIS (provided intensity and organisation are fulfilled). The fact that other countries may be involved in the fight against ISIS (alongside the US) would in no way change the nature of the armed conflict : it would still be a NIAC, since there would be a non-state entity (ISIS) on one side of the fighting (and State entities on the other side).

    Now, the fact that force is used by the US in Syria as ‘legitimate self-defense’ or not (jus ad bellum considerations), has absolutely no bearing on the classification of the situation in IHL.
    True, in that case, it is not Syria which is targeted but ISIS, so the IHL classification may look slightly less straightforward. Still, the mere fact that the US is using force in Syrian airspace/territory, without Syria’s consent, can be considered a ‘hostile act’ (all the more so now that Syria publicly opposed an armed intervention on its territory), and therefore trigger an IAC. (once again, not excluding a potential US/ISIS NIAC).

  16. Nina: Common Article 2 regarding an armed conflict of an international character also speaks to a “Power.” Under the customary laws of war, an armed conflict between a “belligerent” and a state, nation, or other “belligerent” (not an “insurgent”) would be an armed conflict in which all of the customary laws of war apply. E.g., U.S. Dep’t of Army, FM 27-10, para. 8a, etc., etc. It is normal to use CIL as an aid for interpretation of treaties and, therefore, of a treaty term like “Power” (which does not have to be a state). Further, in terms of policies at stake, since all of the customary laws of war apply in an armed conflict between a “belligerent” and a state (as in the case of the U.S. Civil War), it would not be policy-serving to conclude that the word “Power” would not include a “belligerent,” especially because Common Article 3 applies to an insurgency (e.g., an armed conflict not of an international character between an “insurgent” and a state “in the territory of” “one” state (so borders can be relevant after all).
    In any event, U.S. military personnel will only have pow status and “combatant” status and “combatant immunity” for lawful acts of war if they are fighting in an IAC. Therefore, it would be policy-thwarting and nonsensical to conclude that U.S. military personnel are fighting in an armed conflict but the armed conflict is not an IAC. This approach would needlessly place U.S. military personnel in harms way, especially because lawful targetings would be “murder,” “manslaughter,” or involve some other crime.
    Whenever U.S. military personnel are fighting abroad, our Govt. should recognize that they are involved in an IAC.
    There are a large number of writers who also look for any internationalizing factors or elements with respect to an armed conflict. Outside intervention by one or several states and the spill over across borders can be such elements.
    Yes, some textwriters are silly enough to think that the armed conflict in Afghanistan against the belligerent Taliban, involving armed forces from some 50 countries and spill overs into parts of Pakistan, is a NIAC. They are apparently completely oblivious to the consequences for U.S. military personnel and appear to be unmindful of the history of “belligerencies” (if also the distinction between a “belligerent” and an “insurgent”) and the fact that all of the customary laws of war apply to a belligerency but they do not all apply to a mere “insurgency” or NIAC.

  17. p.s. ISIS has not engaged in an “armed attack” against the United States, its embassies abroad, U.S. military personnel, or a sufficient number of other U.S. nationals for us to conclude that the U.S. can engage ISIS as a matter of self-defense. However, contrary to Russia, the U.S. does not need U.N. S.C. authorization to use military force against ISIS in Syria. Article 51 applies because ISIS has engaged in continual armed attacks against the government of Iraq and that government has consented to U.S. participation in legitimate measures of self-defense (per U.N. 51).

  18. Jordan,
    On the Russian point, if Syria considers ISIS’s taking territory and fighting in Syria as an armed attack, it could take the view that Syria’s Article 51 self-defense right was triggered. If the Russians now come ( say Russian bombers come in) in with consent of Syria then those internationalizing factors would make the Syria/ISIS going East across Syria an IAC also along with the Iraq (US and other states)/ISIS going West across Iraq. Article 51 would be working both ways to give combatant immunity for lawful acts of war for all but the ISIS persons like a pincer squeezing and killing ISIS. Am I seeing that right?

    If I am then, two permanent members if the UNSC would be very close to facing each other in different theaters. First, there is the above scenario and second there is the Ukraine and the Baltic states (here some rumbling about there). Crimea is an aggression and the arming of the rebels and Russian troops in Eastern Ukraine we are told about in the press amount to another IAC with Russia perceived as the aggressor. The rebels and the Russians would see the effective control of the government in Ukraine as the creation of a Western client state by illegitimate means I imagine.

    So a face off with Russia in Eastern Europe for Russia’s illegal threat or use of force and a potential face off between American forces and Russian forces on one or the other or both sides of the Syrian/Iraq border in two IAC’s with the consent of the respective client governments.

    Seeing that, one can understand the wish if the White House to get a broad coalition in and out if the region to put non-US forces in place to avoid the risk of armed conflict by the US and Russia in Iraq and Syria.

    ISIS is said to be self-financing and autonomous we are told, i.e. It has no overt or covert support from any states (so we are told). If that is the case then one sees the oxygen being squeezed out if the ISIS balloon.

    Al-Baghdadi can do this analysis and would logically try to block any non-western coalition members from joining out of fear of ISIS foreign fighters coming home to roost or through bribery and corruption.

    I could see Ban Ki Moon stepping in to encourage a resolution that could get both Russian and US support to destroy ISIS while seeking each side respect the borders of Syria/Iraq.

    That would leave to another day the rebels against Assad – who keep dying along with soamy Syrian people. The states are coldly indifferent to that in the Dave of a need to avoid a superpower confrontation.

    Israel wants Assad gone so I doubt they would be helpful to such a UNSC resolution. The legislators in the US would not be amenable to some UNSC resolution that seemed to accept Russia in Syria consistent with their support if the Israel position too.

    So we end back at Syria/ISIS NIAC until Russians come in and the Iraq/ISIS IAC with the US and coalition partners in.

    Good diplomats could make a US Russia deal on this along with Ukraine to walk this back with a common effort to estrou ISIS and leave Assad to fight his domestic rebel battle.

    Just spitballing here.

  19. Ben: aren’t the complexities intellectually wonderful! Re: your first para., yes. Further, Assad has support from a non-state actor Hezbollah and possibly some Iranian military advisers. Yet, unless Iran has internationalized the conflict (still secret?), ISIS would appear to be a mere “insurgent” because no one seems to have recognized ISIS as a “belligerent” and they would not represent an Islamic “nation” etc. What is complicating is the Free Syrian Army. A few years back, there was a rebel entity that many govts. recognized as the legitimate representative of the Syria “people.” The presence of such an entity today could internationalize the conflict against Assad. Yes, Russia and the U.S. should recognize that they would be in an IAC in Syria.
    BREAKING NEWS! Some within the Obama Admin. have now admitted that we are “at war with ISIS”!! But what kind of war??
    The rest of your scenario might make a good exam question later (don’t tell the students).
    A complicating factor for Russia is that Ukraine is a state and Russia has engaged in acts of war against Ukraine and Ukraine has a right of self-defense and collective self-defense against Russia. Russia even meets the ICJ’s “substantial involvement” test regarding Russia’s substantial involvement with the rebels in Ukraine (which means that Ukraine has a right of self-defense against Russia whether or not those tank columns, etc., are Russian).

  20. Nina: another point for consideration regarding limiting language in GC 2 — the IMT at Nuremberg held that a limitation clause in the 1907 Hague Convention No. IV (all those fighting must be parties to the treaty) can limit the reach of the treaty, but will not limit the reach of the customary laws of war that are reflected in HC IV. Nearly all recognize that nearly all (at least) of the IHL provisions of the 1949 Geneva Conventions are now part of the customary laws of war. Therefore, the CIL reflected in the GCs should reach as far as the customary laws of war reach, e.g., without treaty limitations concerning Parties and Powers. This recognition seems to be behind the expectations of the vast majority of states and the ICRC that the customary laws of war or IHL reflected in the GCs that prohibits sending one’s population into occupied territory and the annexation of occupied territory applies to a state and its nationals if that state is an occupying power whether or not the territory that is occupied is that of a Party to the GCs.
    Of course, it is also relevant the HC IV does not contain treaty-based limitations regarding occupied territory that one can see in the text of GC 2 regarding Parties — and HC IV also reflects CIL.

  21. Thanks very much for the further layers Jordan. Alas, I told my students they should read opiniojuris so the cat is out of the bag for this question ! Just saw an article that says that for 25 years every President of the Unjted States has come before the American people in the evening announcing we are bombing Iraq. Deep!

  22. On the Regional coalition, I heard on CNN that ISIS has 40 Turkish diplomats – their blackmail to block regional participation by Turkey. The hostage mix becomes their leverage to each nation of each country they want to dissuade. Cold game of ruthless power playing. UNSC resolution on violations of diplomatic immunity and hostage taking might be supported against ISIS as nonstate actor. ISIS might be made to release all hostages, failing which “any means necessary” resolution. ISIS might not release and face any means necessary or release and face next step of destruction. Either way, they are screwed. If I were them I would be looking for local game changer or overseas game changer. Whatever they do though, they are screwed.

Trackbacks and Pingbacks

  1. […] at Opinio Juris, Kevin Jon Heller has already penned a criticism of Mike’s conception of the law of self-defense, which describes the flaw in Mike’s analysis […]

  2. […] Dès lors, en raison des difficultés susmentionnées, peut-on considérer que les autorités syriennes n’ont ni la volonté, ni la capacité d’agir contre l’EI ce qui permettrait aux États-Unis d’agir directement sur le territoire syrien? Il convient de rappeler que ce standard est appliqué par les États-Unis dans le cadre de leurs frappes létales entreprises contre des terroristes constituant une menace imminente et localisées en-dehors d’une zone d’hostilité active. En l’espèce, le « problème » est que les autorités syriennes ont justement manifesté leur volonté de combattre l’EI et de coopérer avec les États-Unis dans cette guerre. Pour Ryan Goodman du blog Just Security, les États-Unis pourraient contourner cette difficulté en remettant en cause la bonne foi du gouvernement de Bashar el-Assad qui a joué un double jeu avec l’EI. De plus, une aide des forces militaires et des services de renseignement syriens seraient susceptibles d’entraver l’efficacité d’une action armée contre l’EI. Selon Michael Lewis, le standard s’applique en raison de l’incapacité du gouvernement à contrôler son territoire. Les autorités syriennes étant incapables d’empêcher l’EI de planifier, de préparer et d’exécuter des attaques en Irak, leur volonté de coopérer avec les États-Unis importe peu. Si ces argument sont intelligibles dans le contexte américain, ils sont à relativiser en droit international, le test de l’absence de volonté ou de capacité n’étant pas consensuel. […]