Kevin Heller, Opinio Juris blog posts on “unwilling or unable” | Samuel Moyn | August 02, 2016


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Kevin Heller, Opinio Juris blog posts on “unwilling or unable”

Ashley Deeks’ Problematic Defense of the “Unwilling or Unable” Test

Kevin Jon Heller, Opinio Juris (blog), December 15, 2011

…The essay is a very interesting read, and Deeks should be commended for trying to think systematically about what the “unwilling or unable” test would require in practice.  There is, however, a fundamental problem with the essay: it completely fails to establish its thesis that “[i]nternational law traditionally requires the victim state to assess whether the territorial state is ‘unwilling or unable’ to suppress the threat itself.”  The current state of the legal regime governing extraterritorial attacks against non-state actors is one of the most difficult and controversial areas of international law, requiring a careful analysis of state practice and opinio juris.  Unfortunately, such an analysis is absent from Deeks’ essay.  Instead, Deeks relies on a mistaken understanding of neutrality law, provides little more than a few isolated examples of extraterritorial attacks that have ostensibly been justified under the “unwilling or unable” rubric, and ignores all of the contrary examples. …

The real question, then, is what the customary rule governing extraterritorial force against NSA might be in the post-Charter world.  Deeks discusses three different positions on the relationship between Article 2(4) of the UN Charter’s prohibition on interstate force and Article 51’s exception to that prohibition for acts of self-defense in response to an armed attack: (1) that the armed attack giving rise to the right of self-defense must involve a state; (2) that the armed attack can involve a non-state actor (NSA), but the actions of the NSA must be attributable to a state; and (3) that the armed attack can involve a NSA and does not require any kind of attribution to a state.  Deeks says that a “premise” of her article, supposedly based on “extensive state practice,” is that the third position is correct.  I’ll return to that supposed state practice below, but it’s worth noting here that Deeks attributes the three positions on self-defense to “groups of scholars” — and then relegates to a footnote (n. 17) the rather important fact that the second position is the one that has been specifically endorsed, in multiple cases, by the International Court of Justice.  ICJ decisions are not themselves primary sources of international law, but the failure to discuss those decisions is a serious problem with Deeks’ essay — especially as the essay does not even mention the Nicaragua case, in which the ICJ held the most clearly that state attribution is required.

So what is this “extensive” state practice that Deeks cites as evidence that the “unwilling or unable” test reflects customary international law?  Actually, it’s not extensive at all.  In the essay’s introduction, she mentions (pp. 4-5) Russia’s attacks on Chechen rebels in Georgia; Israel’s attacks on Hezbollah and the PLO in Lebanon; and Turkey’s attacks on the PKK in Iraq.  Later on, she mentions the Soviet Union’s 1921 attack on White Guard bands in Outer Mongolia; U.S. attacks on Viet Cong soldiers in Cambodia during the Vietnam War; U.S. attacks on al-Qaeda in Afghanistan and the Sudan; and Colombia’s attacks on FARC in Ecuador.  That’s it.  Pretty weak tea indeed — especially when we factor in the international response to many of those uses of force against “unwilling or unable” states, such as the Organization of American States’ unequivocal condemnation of Colombia’s attacks on FARC as a violation of Ecuador’s sovereignty.

More importantly, Deeks simply ignores the numerous instances in which the Security Council and/or states have condemned extraterritorial uses of force against NSAs whose actions were not attributable to the state whose territory was attacked.  Examples include Israel’s 1985 raid of a PLO headquarters in Tunis; Iran’s cross-border attacks throughout the 1980s on Kurdish fighters in Iraq (which were vociferously condemned by the U.S.); and Rwanda’s attacks in the late 1990s on Hutu rebels in the DRC.

To be sure, it appears that customary international law is slowly evolving away from the Nicaragua standard, especially in the wake of 9/11.  But it is far from clear whether that standard has been replaced by the “unwilling or unable” test.  …

Indeed, what is most surprising about Deeks’ essay is that Deeks herself admits that the “unwilling or unable” test cannot be considered customary international law.  If you look at footnote 55 of her essay, you find this remarkable statement:

I have found no cases in which states clearly assert that they follow the test out of a sense of legal obligation (i.e., the opinio juris aspect of custom), nor have I located cases in which states have rejected the test.    Even if one concludes that the rule does not rise to the level of custom, however, the rule makes frequent appearances in state practice and therefore is the appropriate starting point from which to determine how the norm should develop.

That is a remarkable admission — and one that directly contradicts Deeks’ thesis that “[i]nternational law traditionally requires the victim state to assess whether the territorial state is ‘unwilling or unable’ to suppress the threat itself.”  If there is no opinio juris that supports the “unwilling or unable” test, it is difficult to argue that the test reflects customary international law — especially in light of the consistent and contrary pre-9/11 state practice and opinio juris that both Tams and Ruys discuss.

The bottom line: de lege ferenda, there is much to recommend Deeks’ essay.  De lege lata, however, it completely fails to make its case.


The Seemingly Inexorable March of “Unwilling or Unable” Through the Academy

Opinio Juris (blog), March 6, 2015

by Kevin Jon Heller

How does an international-law doctrine become conventional wisdom without actually having support in the practice of states? It starts with one article asserting the doctrine, but failing to defend it. Then another article makes the same claim, citing only the first article. And then another. And another. And so on — until no one remembers that the first article did not actually identify any state practice at all.

So it is with the “unwilling or unable” test, as indicated by an otherwise quite good new article in the Journal of Conflict & Security Law entitled “Jus ad Bellum and American Targeted Use of Force to Fight Terrorism Around the World.” Consider (p. 228):

With regard to the use of self-defence against private actors located in another state, two consequences flow from the requirement of necessity. First, state practice indicates that the exercise of self-defence against the private actor is conditioned on the inability or unwillingness of the authorities in the host state to stop the private actor’s activities.98 Obviously, if the host state both can and will stop the activities in question, it will not be necessary for the victim state to resort to the use of force.

I’ve left the footnote number in, because it refers to precisely one source: Ashley Deeks’ essay “Unwilling or Unable: Toward an Normative Framework for Extra-Territorial Self-Defense.” An essay in which, as I have pointed out, the author openly admits that she “found no cases in which states clearly assert that they follow the test out of a sense of legal obligation.” (The US and UK have formally endorsed the unwilling or unable test since Deeks’ article was published.)

To be sure, the new article elaborates a bit on the “support” for the unwilling or unable test. But none of that support involves the practice of states — nor does the article acknowledge the inconvenient fact that the Arab League (22 states) has formally rejected the test (post-9/11, even). Instead, it simply says this (p. 229):

The test is widely supported in the literature, and it is also mentioned in two 2013 UN reports by, respectively, the UN Special Rapporteur on extrajudicial, summary or arbitrary executions and the Special Rapporteur on the promotion and protection of human rights and fundamental freedoms while countering terrorism. It also features among a series of “Principles Relevant to the Scope of a State’s Right of Self-Defense Against an Imminent or Actual Armed Attack by Nonstate Actors” proposed by the former legal adviser of the United Kingdom Foreign & Commonwealth Office, Daniel Bethlehem.

“Instant custom”? How passé. Who needs state practice at all? And please don’t bore us by pointing out contrary practice by a bunch of benighted states in the Global South. All we really need are enough scholars, special rapporteurs, and former legal advisors in the Global North willing and able to endorse a particular doctrine and poof — customary international law.


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August 02, 2016

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Samuel Moyn

Harvard Law School

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