German Parliament decides to send troops to combat ISIS − based on collective self-defense “in conjunction with” SC Res. 2249

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On 4th December 2015, after a parliamentary debate on 2d December, the German Parliament decided, with 445 positive votes (146 negative votes and seven abstentions), to honour the German’s Government’s formal request (BT Drucksache 18/6866 of 1st Dec. 2015 ) to send up to 1200 troops to combat ISIS. A formal parliamentary decision to deploy military abroad is required by the German Constitution (Basic Law) and a German 2005 law (Parlamentsbeteiligungsgesetz) which codifies prior constitutional case law.

The international legal basis for the deployment decision, as officially claimed by the Government, is “Art. 51 of the UN Charter in conjunction with Art. 42(7) TEU as well as resolutions 2170 (2014), 2199 (2015), 2249 (2015) of the Security Council.” In its request to Parliament, the Government explained that action against IS (by the US, Australia, the UK, and France) “in exercise of collectives self-defence under Art. 51 of the UN Charter is covered by resolution 2249 (2015).” (BT Drs. 18/1866, p. 3). The EU-assistance clause as invoked by France on 13th November, to which all EU member States responded on 17th November with the promise for assistance, has been analysed here by Carolyn Moser. The substance of the IS resolution 2249 has been analysed on EJIL talk! by Marc Weller, by Dapo Akande and Marko Milanovic.

As Dapo and Marko have pointed out, the novelty of SC res. 2249 is not so much that it does not mention Chapter VII, but rather that it does not “decide” or “authorize” but only “calls upon” Member States “to take all necessary measures”. The omission to mention Chapter VII, together with the softer verb “call”, deliberatively leaves open whether the resolution would allow for coercive measures without Syrian consent or not. Thereby, reservations by Russia and China against an infringement of Syrian sovereignty, as their delegates had voiced at the two previous occasions in the Security Council, when they vetoed draft resolutions which had foreseen an arms embargo against Syria (2011) and humanitarian assistance to the civilian population in Syria (2012), could be appeased. It is by no means clear that this resolution could function as an independent basis of military action (see for a negative answer Jasper Finke).

German Parliamentary Debate of 2d December 2015

During the Parliamentary debate, the German minister of foreign affairs, Frank-Walter Steinmeier, answered to the critical remark of a member of the left party that “normally, the right to self-defence is interpreted as allowing defence against a State attack (…) Does the German government interpret Art. 51 in the sense that one may take military means against any terrorist act?” as follows: “Very clearly, to the question of Art. 51 of the UN-Charta – self-defence – I reply: We are here not in a seminar (…) After in total eight attacks which happened in France, this is not the hour to explain to the French (…) that they need not feel attacked.” (column 13879, my translation).

Another member of the governing Christian democrat party insisted that international law is “no suicide pact”. It does not require us to let us and our friends be slaughtered by terrorists because unfortunately we do not yet have the ideal Chapter VII resolution. Art. 51 of the UN Charter rather says clearly that we are allowed to defend us, and we may help our friends.” (column 13896, my translation).

Yet another member of the Christian democrat party appealed to the opposition to “put aside, in the sign of solidarity, from lecturing in a filburster-like fashion, nitty-gritty, and seminar-style on a differentiated analysis of the legal question.” (column 13891, my translation).

But what is the legal question?

The legal question is, first, whether Article 51 allows for self-defence against non-state actors. Since 2001, state practice has increasingly leaned towards answering this question with a “yes”. It is well known that the two Security Council resolutions taken in the aftermath of 9/11 had mentioned self-defence only in their preambles and thus not fully accepted that the US American legal attacks on Afghanistan against Al Qaeda were really covered by self-defence as claimed by the United States. Also, the ICJ case law, is I submit, most plausibly read as not clearly answering in the negative but as having left open the question in the Israeli Wall opinion (2004) and notably in the famous para. 147 of the judgment DR Congo v. Uganda (2005) on “self-defence large-scale attacks by irregular forces”.

But since the rise of IS and their increasing perpetration of attacks in various States outside the territories which they are directly controlling, a growing number of States has invoked individual or collective self-defence against IS. States can rely on the open wording of Art. 51 which speaks of an armed attack but not of an armed attack by a state. But the well-known problem is that any “defensive” reaction against IS will inevitably affect the territory, infrastructure, and population of Syria. Such sacrifice by Syria would need an additional justification. At this point, the declaration that Syria is “unwilling or unable” to prevent attacks emanating from IS, as stated by the USA, Canada, Australia, and Turkey in their letters to the Security Council (S/2014/695; S/21015/221; S/2015/693; S/2015/563), comes into play. The term “unwilling or unable” has been used by those states (but not, e.g. by the UK and France) without explaining its legal meaning. As it is well rehearsed, four legal functions of the formula are conceivable but ultimately not really convincing. First, it could constitute a criterion of attribution of IS attacks to Syria – but this seems absurd assuming Syria’s sheer incapability despite willingness. Second, the formula cannot, again for fairness reasons, explain Syrian responsibility for its own omissions if the State is indeed incapable. Third, it seems strange to accept some kind of forfeiture of Syrian sovereignty because the sheer inability of Syria. Finally, although the Syrian “inability” may give rise to the “necessity” of military reaction (in the realm of Art. 51 UN Charter), this is a limiting condition and no free standing authorisation.

So far, only a few States − but not Germany − have protested against the rapid rise of the “unwilling or unable” formula. The silence of the vast majority of states is in normative terms problematic, because it risks to be interpreted as implied acquiescence to an extensive interpretation of Art. 51 of the UN Charter. Worse even, the explicit and positive endorsement of the broad reading of self-defence, as just done by Germany, too (after notably the UK, as analysed here by Marko) might constitute a further – even not very stable –building block of subsequent practice (Art. 31(3) lit. b) VCLT). It is not unlikely that this practice, if it is not outbalanced by protesting statements will from now on guide the application of Art. 51 UN Charter − for the better or worse.

Another legal question of course the “imminence” of attacks to be expected by IS. Art. 51 does not allow punitive military action for the past attacks of 13th November. States may only rely on self-defence now by either claiming a “permanent attack” (see Marc Weller) or imminent incidents. One should keep in mind that especially the reliance on self-defence by the UK after the targeted killing of two individuals came frightfully close to a “pre-emptive self-defence” argument in the style of the 2002 “Bush doctrine”, as Nehal Bhuta has pointed out on this blog. But after the 13th November attacks, the situation looks different. IS has explicitly announced new attacks so that imminence can hardly be denied.

The Parliamentary scientific service had on 23th and 30th November 2015 issued a two-part legal opinion on the question of State defence against terrorists and the legal implications of SC res. 2249 (2015) (WD 2-3000-2013/15). In this legal opinion, the service came to the conclusion that “obviously, last but not least against the background of the recent Paris attacks – an evolution of customary law” has occurred in the direction of admitting self defence against non-state actors (p. 14, my translation). The government and parliament heavily relied on this legal opinion and on that basis claim that the German decision is fully covered by international law. (The claimed constitutional law basis of the deployment is Art. 87a (2) of the German Basic Law (“defence”), and – arguably – also Art. 24 (2) of the Basic Law (“collective security”) if read broadly, as the Government explicitly does in its request). It is an interesting twist in European history – and a sign of the success of European integration – that Germany, a country which after the Second World War has been so extremely reluctant to take military action abroad, now does so to help France.

I think that the German decision is indeed covered by international law, but that this cover is really thin. It is hard to build on the law “as it stands”, because the law is moving. Still, the emergence of novel customary law, as assumed by the German legal service, would normally seem to require more time than 15 years (since 2001) – if we do not buy into the “instant custom” theory.

A normative assessment of the legal grey zone which could guide policy advice is difficult. On the one hand, it can hardly be denied that IS has the capacity to launch armed (suicidal) attacks of high scale and intensity, with the threat exacerbated by their relatively novel means. Populations all over the world deserve protection from such threats.

On the other hand, the risk of escalation and of a spiral of violence is obvious. And history cannot “teach” any lesson on this question. While on the one hand, the illegal unilateral Iraq intervention by the USA in 2003 surely fuelled fundamentalism in the region, it is also plausible that the failure of the United Nations to intervene under the heading of R2P in Syria, or of the US and the UK under the banner of humanitarian intervention, have been important factors for the rise of IS. But all these reflections will remain speculative. We will never be able to “prove” that IS would be less strong if only in 2011 or 2012 military action in Syria had been taken.

In any case, the criteria of unwillingness and/or inability are too vague to set an effective limit on the lawfulness of “defensive” strikes against terrorist groups. States which seek to contain military reaction, or which fear that they themselves might at some point be qualified as “unable or unwilling” are therefore well advised to protest against the broad interpretation of self-defence.

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Jordan says

December 8, 2015

Thank you Anne. There is, of course, no "unwilling or unable" limitation of the inherent right of self-defense in Article 51 of the U.N. Charter or predominant practice coupled with opinio juris (see also and etc.). Further, as the SSRN articles and others note, there is no need for Syrian consent as a limitation of the inherent right of self-defense or collective self-defense against ongoing armed attacks by the NSA "insurgent" ISIS or any other NSA attacker. The Caroline case has been misread and misused with respect to so-called anticipatory self-defense against an "imminent" armed attack, when actually, the Caroline incident involved a series of prior and continuous NSA armed attacks on Canada emanating from the U.S. when the U.S. was not responsible for the NSA attacks, when the U.S. and the U.K. were not at war, when the U.S. did not give consent to the U.K. use of force in self-defense (see ibid and 45 Geo. J. Int'l L. 411 (2014), available at -- especially at pages 422-23 & fn. 22 re: Lord Campbell's claim that the U.K. could selectively target a NSA's artillery battery in the U.S. that was firing across the border at U.K. soldiers).
Yes, preemptive self-defense and the Bush doctrine have been widely condemned -- and so should the Obama doctrine regarding "imminent threat" because and imminent threat is not even a real threat, much less an imminent armed attack. See pages 418-21.
ISIS is merely an "insurgent" (it has never been recognized as a state, nation, or belligerent), but the armed conflict in Syria and Iraq is an armed conflict of an international character to which all of the customary laws of war otherwise apply. See, e.g., regarding the internationalization of an armed conflict and the circumstance where an armed conflict takes place within two or more states (cannot be a NIAC).

Nicolas Boeglin says

December 8, 2015

Dear Professor Peters: Many thanks for this extremely useful article on German recent discussion and finally approval, and, as you says, the "thin" legal base from the perspective of international law. My question has to do with a the existing difference between France/UK operations (bomb attacks on ISIS positions and targetted killing of suspects in Syria, nationals included) and German operations: we read that "“According to the draft mandate, Germany is to provide immediate support with satellite reconnaissance, and in the future with reconnaissance planes such as the German Air Force’s Tornado aircraft. Among other things, this will help to detect cross-border movements and provide intelligence about the actual size of the area of operations and ISIS’ sphere of influence. Moreover, the draft specifies that Germany is to provide tankers for air-to-air refuelling and a frigate to escort the French aircraft carrier, as well as personnel for staff posts and headquarters”. Source: In your view, does this recent decision close the door for another kind of military operations by German aircrafts? Yours sincerely

Leander Beinlich says

December 11, 2015

Dear Prof. Peters,

when reading your blog I was wondering in how far the „German“ reasoning for the deployment of armed forces is in some way contradicting the arguments given by both the UK and the US governments. The German government relied on the legal opinion given by the Parliamentary Scientific Service, which generally tried to justify actions against terrorist groups such as ISIL by referring to SC Res. 2249, to Art. 51 UN Charter and to developing customary law. While explicitly stating that the Resolution is not mandating the Syria intervention in itself, the Scientific Service nevertheless comes to the conclusion that the Resolution allows for states to “invoke a right to self-defence” against ISIL without having to wait for consent of the Syrian government.

Irrespective of the question, whether the Resolution in conjunction with developing customary law can (and should) be understood in that way and can therefore legitimize actions against ISIL, the deployment of German troops was in the end based on both the collective security approach and the EU-assistance clause. So, as I see it, the German government is not stating that it has a right to self-defence but rather derives it from a right to self-defence of France.

In this, I think, one could see a contradiction to the reasoning by US and UK governments as they invoke an independent right to self-defence (if I am not mistaken), while the German government eventually does not base the deployment of the German Bundeswehr on such a right.

Besides, I think that the legal justification of the German government and the legal opinion by the Scientific Service are clear in one way. That is, that the German government - despite public assertions of a strong and clear legal basis for the deployment - is perfectly aware that the legal basis for the deployment of the German Bundeswehr is indeed (very) “thin”, as you said in your blog. That the government in the end does not refer to a right to self-defence arising from the Resolution and customary law, but to the assistance clause, is in my view indicating that the German government is not really sure, whether the Resolution and customary law are really enough a legal basis for the deployment of the Bundeswehr (and if - given it will be legally challenged - it would convince the German Constitutional Court). This uncertainty could also be observed during the debate in Parliament and the remarks by German Foreign Minister Frank-Walter Steinmeier (“we are here not in a seminar !”), which you also mentioned in your post.

In any way, the recent decisions to deploy military armed forces to Syria (and Mali) could reinforce claims for constitutional changes in order to include a clear legal basis for the use of force and the deployment of the Bundeswehr in the German constitution (a so-called “Wehrverfassung”), which at the moment only roughly provides (written) rules for that subject.