In the part of the judgment dedicated to general international law,Footnote 1 the Court insisted on the inter-state character of the principle of territorial integrity. According to Paragraph 80 of the opinion:
Several participants in the proceedings before the Court have contended that a prohibition of unilateral declarations of independence is implicit in the principle of territorial integrity.
The Court recalls that the principle of territorial integrity is an important part of the international legal order and is enshrined in the Charter of the United Nations, in particular in Article 2, paragraph 4, which provides that:
‘All Members shall refrain in their international relations from the threat or use of force against the territorial integrity or political independence of any State, or in any other manner inconsistent with the Purposes of the United Nations.’
In General Assembly resolution 2625 (XXV), entitled ‘Declaration on Principles of International Law concerning Friendly Relations and Co-operation among States in Accordance with the Charter of the United Nations’, which reflects customary international law (Military and Paramilitary Activities in and against Nicaragua (Nicaragua v. United States of America), Merits, Judgment, I.C.J. Reports 1986, pp. 101–103, paras. 191–193), the General Assembly reiterated ‘[t]he principle that States shall refrain in their international relations from the threat or use of force against the territorial integrity or political independence of any State’. This resolution then enumerated various obligations incumbent upon States to refrain from violating the territorial integrity of other sovereign States. In the same vein, the Final Act of the Helsinki Conference on Security and Co-operation in Europe of 1 August 1975 (the Helsinki Conference) stipulated that ‘[t]he participating States will respect the territorial integrity of each of the participating States’ (Art. IV). Thus, the scope of the principle of territorial integrity is confined to the sphere of relations between States.Footnote 2
The aim of this paper is not to determine whether the Court was ‘right’ or ‘wrong’ in its interpretation of existing international law.Footnote 3 Rather, I will attempt to assess the legal consequences of this paragraph. It will be shown that this section of the advisory opinion reflects a very traditional conception of international law. Indeed, the Court refused:
• first, to challenge the classical argument of the ‘neutrality’ of international law in regard to secession;
• second, to extent Article 2(4) of the UN Charter beyond relations between states;
• third, to weaken the principle of territorial integrity by accepting the argument of ‘remedial secession’,
• and, fourth, to assert limitations to the means that the parties of a secessionist conflict may use.
1. Insisting on the classical argument of ‘legal neutrality’
Traditionally, international law remains neutral in regard to secession: it neither prohibits nor authorizes it.Footnote 4 Secession itself is regulated by national, not international, law, even if human rights law (and possibly the law of armed conflict) is applicable in such situations.Footnote 5 During the proceedings before the Court, the supporters of Kosovo's independence insisted on this ‘legal-neutrality’ argument.Footnote 6 By contrast, some other states contended that the principle of territorial integrity had recently been applied in secessionist conflicts.Footnote 7 They referred to several Security Council resolutions, not only in the Serbia/Kosovo case, but also in those of Georgia/Abkhazia and South Ossetia, Bosnia–Herzegovina/Republika Srpska, Azerbaïjan/Nagorno-Karabakh, and other similar conflicts. They also asserted that the application of the principle of territorial integrity to non-state groups or to individuals had been recognized in various GA resolutions,Footnote 8 treaties,Footnote 9 or regional instruments.Footnote 10
By insisting on the strictly inter-state character of the territorial-integrity principle, the Court refused to challenge the ‘legal-neutrality’ thesis.Footnote 11 This latter expression is not mentioned as such by the Court. Yet this thesis clearly appears in paragraph 79 of the opinion, in which the Court considers that there is no emerging customary prohibition of secession.Footnote 12 This reflects a strong reluctance of the Court to admit the emergence of a new customary rule. It appears that according to the Court, Security Council resolutions and other conventional or non-conventional instruments in which territorial integrity was applied to non-state actors are not sufficient to establish an evolution of custom in this area.Footnote 13 It seems that these texts were too ambiguous, and that some of them were only applicable in the situations at stake.Footnote 14 This very strict methodology must be emphasized. The controversies over the conditions of evolution of the rules enshrined in the UN Charter are well known.Footnote 15 On the one hand, some authors use an extensive approach; they contend that a limited practice (especially if supported by major states) is sufficient to establish an evolution of the rule.Footnote 16 On the other hand, others promote a far more restrictive method, by requiring a general practice and an opinio juris shared by all UN members.Footnote 17 The Kosovo AO confirms that the Court clearly prefers the latter approach, which is the classical one.Footnote 18 And it is not surprising that, using this method, the Court refused to admit some new and extensive interpretations of the existing law.
2. Reaffirming the inter-state character of the rule set forth in Article 2(4) of the UN Charter
Traditionally, the scope of Article 2(4) of the UN Charter is considered as confined only to states.Footnote 19 By contrast, military operations led by – or directed against – non-state actors are supposed to be governed by the domestic law of the state concerned. Since the early 2000s, this classical conception is challenged in the name of the necessity to adapt the law to new political realities.Footnote 20 According to scholars following this new way of thinking, the increasing threat posed by terrorist or other non-state groups should lead to a new interpretation of the rule prohibiting the use of force, which should be extended beyond inter-state relations. Article 2(4) of the Charter should therefore be rewritten, or at least reinterpreted, in order to meet the new realities of a post-national world. Against this background, it is significant that the Court strongly insists on the inter-state character of this provision. After quoting Article 2(4) in extenso, and after insisting on the inter-state character of the rule prohibiting the use of force as reflected in Resolution 2625 (XXV) and in the Helsinki Final Act, the Court concludes that ‘Thus, the scope of the principle of territorial integrity is confined to the sphere of relations between States’.Footnote 21 Paragraph 80 of the advisory opinion appears therefore incompatible with any attempts to ‘denationalize’ or ‘privatize’ Article 2(4). During the proceedings, most states explicitly or implicitly confirmed that this article only applies in ‘international relations’, namely between states.Footnote 22 And, interestingly, no state contended that jus contra bellum should be extended to non-state actors.Footnote 23
It could certainly be argued, of course, that the ‘Kosovo case’ was not a case about the use of force, but a case about secession, and that the Court wanted to focus on the ‘territorial-integrity’ principle, not on the general prohibition on the use of force. This might be true, but it is nonetheless obvious that the Court makes (in paragraph 80) a very clear and express reference not only to Article 2(4), but also to other famous international law instruments, as containing an obligation incumbent upon states to refrain from using force against other sovereign states. The inter-state character of the rule prohibiting the use of force is thus confirmed in a very clear, although indirect, way. By contrast – and this would have been possible if it had wished to limit the effect of its statement – the Court did not:
• specify that this analysis was limited to relations between a state and a secessionist group, and could not apply to non-secessionist groups, such as terrorists;
• refer to the principle of territorial integrity in a general and abstract way, but chose to tie it to Article 2(4) of the UN Charter.
The Court preferred to quote this provision in extenso by insisting in general terms on its ‘inter-state’ character. This aspect of the Kosovo AO sounds like a reminder of its previous case law. In the Wall Advisory Opinion,Footnote 24 as in the Congo–Uganda decision,Footnote 25 the Court already refused to apply jus contra bellum to non-state actors. At that time, the Court was criticized by some judges in their separate opinions. By contrast, in the Kosovo AO, no judge contested, nuanced, or mitigated the general statement made by the Court on the inter-state character of Article 2(4).Footnote 26 To this extent, the opinion can be viewed as another precedent against any reinterpretation of Article 2(4) of the UN Charter. And, as it will be demonstrated in the next section, this opinion cannot be invoked in support of another attempt yet at extending another classical rule of international law.
3. Challenging the ‘remedial-secession’ doctrine
The ‘remedial-secession’ argumentFootnote 27 was invoked by several states in their written or oral observations before the Court.Footnote 28 This argument is mainly based on an a contrario interpretation of the ‘saving clause’ contained in General Assembly Resolution 2625 (XXV):
Nothing in the foregoing paragraphs shall be construed as authorizing or encouraging any action which would dismember or impair, totally or in part, the territorial integrity or political unity of sovereign and independent States conducting themselves in compliance with the principle of equal rights and self-determination of peoples as described above and thus possessed of a government representing the whole people belonging to the territory without distinction as to race, creed or colour.Footnote 29
According to some states, the Kosovan people would have been the victim of a serious violation of their internal right to self-determination, mainly in the late 1990s. They would therefore be entitled to invoke an external right to self-determination, which would provide a legal basis for their declaration of independence. However, this view was contested by numerous other states.Footnote 30 According to these, the ‘remedial-secession’ thesis cannot be deduced either from GA Resolution 2625 (XXV) or from international practice.Footnote 31 It should therefore not be accepted and, even if it were, it would not be applicable to the situation of Kosovo at the time of the unilateral declaration of independence, in 2008.
In paragraph 83 of its opinion, the Court considers that the ‘debates regarding the extent of the right of self-determination and the existence of any right of “remedial secession”’ are ‘beyond the scope of the question posed by the General Assembly’.Footnote 32 Officially, the Court thus did not pronounce on this matter.Footnote 33 Nevertheless, by insisting on the inter-state character of the principle of territorial integrity, the Court indirectly challenged the remedial-secession doctrine. According to this doctrine, in certain particular circumstances, international law would ‘authorize’ (GA Resolution 2625) a dismembering of the territory of a sovereign state. This logically presupposes that territorial integrity must in principle be respected by the secessionist entity, this entity being exceptionally entitled to infringe this principle as a ‘remedy’ to a previous violation of its international right to self-determination. This is obviously not compatible with paragraph 80 of the opinion of the Court, which precludes any applicability of the rule between the state and the group concerned. In other words, as the state cannot invoke its territorial integrity to oppose a secessionist group, this group cannot invoke a right to infringe the territorial integrity of the state targeted. The principle of territorial integrity is simply not applicable; it can therefore not be violated and a right to violate it is not logically possible. Here, again, secession as such is not governed by international law, which remains ‘neutral’.Footnote 34 Hence, the legal-neutrality thesis as reaffirmed by the Court seems incompatible with the ‘remedial-secession’ argument and, more generally, with any kind of ‘right to secede’.
4. Avoiding condemning unilateral actions in an internal conflict
Against this background, it is clear that the Court refused to consider Kosovo as a ‘special case’ or a sui generis situation.Footnote 35 According to the Court, this case must be governed by the traditional rules of general international law. And these rules can be expressed by the legal-neutrality thesis, which must be applied in the Kosovo case, as in other secessionist conflicts.
This means, of course, that Kosovan authorities did not violate international law either by declaring independence (as expressly stated by the Court)Footnote 36 or by exercising their enforcement powers to assert their control over the territory. But, this also means that Kosovo cannot itself invoke its territorial integrity to oppose either a possible declaration of independence by a secessionist group inside its territory or the use of non-peaceful means by this same group to reach its aim.Footnote 37 Article 2(4) of the UN Charter is not applicable inside Kosovo and it is somewhat surprising that territorial integrity was invoked by those who refuse the application of the principle when invoked by Serbia.Footnote 38 What are the consequences thereof in the relations between Kosovo and Serbia?Footnote 39 If Kosovo is a state, territorial integrity and Article 2(4) of the Charter are relevant legal principles.Footnote 40 But if Kosovo is not a state – and this is far from being ruled out by the CourtFootnote 41 – these principles do not apply. In the latter hypothesis, Serbia could, of course, help the Serbs living in Kosovo to resist the Pristina authorities, and even to use military means to resolve the issue.Footnote 42 On the other hand, the Kosovan government would not be precluded from using force in order to establish its authority on every part of ‘its’ territory, or even on parts of the Serbian territories that were never situated in the province. This is, once again, a traditional application of the ‘legal-neutrality’ argument. The same pattern is, of course, applicable everywhere.Footnote 43 If one relies on paragraph 80 of the Kosovo AO, no state in the world can invoke its territorial integrity to oppose a secessionist movement. And a declaration of independence – like an official governmental declaration condemning it – cannot be declared either ‘in conformity with’ or ‘in violation of’ international law. Against this background, if the parties do not have a ‘right’ to use force, then they do not violate Article 2(4) of the UN Charter by using it.
Of course, these conclusions are without prejudice of a possible Security Council resolution. Acting under Chapter VII of the Charter, the Security Council can prohibit the parties to use force and can establish a peaceful mechanism to resolve the issue. Serbia and many other states asserted that SC Resolution 1244 (1999) should be interpreted as an illustration of this possibility.Footnote 44 According to these states, by referring to the territorial integrity of Yugoslavia and by establishing an international administration in Kosovo, the Security Council actually prohibited the parties to act unilaterally. Following this lex specialis, Kosovo could not declare its independence, whereas Serbia could not use non-peaceful means to fight the secessionist movement. The Court, however, interpreted SC Resolution 1244 in a very different way.Footnote 45 As we know, and this will be commented on in other papers in this symposium,Footnote 46 it considered that the text of this resolution (and, in particular, the reference to the territorial integrity) was too vague to entail a prohibition of secession. The Court's position seems rather surprising, as it could be seen as a license to use unilateral – and possibly non-peaceful – means, even when the Security Council has adopted resolutions founded on Chapter VII of the UN Charter. Hence, and this is another aspect of the Kosovo AO, it is clear that every resolution requires to be strictly interpreted.Footnote 47 Even if the Security Council affirms the necessity to respect the territorial integrity of a state, this does not mean that this principle is applicable in the relations between this state and a secessionist group. Even in this case, thus, the classical inter-state paradigm of international law still remains.