20 years since the Kosovo war: what was – and what remains


Monthly blog series by Hans-Joachim Gießmann, Executive Director at the Berghof Foundation

It is exactly 20 years since NATO carried out airstrikes in the former Yugoslavia. With no mandate under international law and in the face of strong opposition from two permanent members of the Security Council, Russia and China, NATO attempted to force an outcome that had not been achieved during the preceding weeks of negotiations: Belgrade’s surrender of military control over Kosovo.

The fact that the campaign was a deliberate breach of international law is no longer seriously disputed. Whether the war was nonetheless justified, is still contested, 20 years on.

It is primarily political and moral arguments that are marshalled to justify the war: The oppression and increasing expulsion of the Kosovo Albanians would not have ended without NATO’s intervention. After the breakdown of negotiations between the Kosovo rebel army and the government of Yugoslavia, abuse and harassment by the Serbian police and armed forces would simply have escalated.

It is claimed that NATO gave Yugoslavia’s leader Slobodan Milošević time to fall into line – time which he chose not to use. Although NATO acted without a Security Council mandate, it did so out of a sense of responsibility and in compliance with principles of international law, mainly to protect the people of Kosovo from further attacks. After all, law should not serve to perpetuate gross injustice, so the argument goes. Moreover, the UN Security Council issued a mandate ex post.

Criticism of the NATO campaign mainly focuses on the precedent set under international law, but political and moral arguments are invoked as well. Wars of aggression are prohibited under international law. It is true that the two exceptions to the prohibition of the use of force did not apply here: this was not self-defence under Article 51 of the UN Charter, nor had the Security Council mandated measures under Articles 39-42 that would have justified the use of force against a sovereign member of the United Nations.

Politically, it is argued that there was no reason to launch the strikes as early as on 24 March 1999, except for the fact that NATO’s credibility was at stake. It had previously announced air strikes in September 1998 if the negotiations failed – even though the talks had not yet commenced at the time. Under these circumstances, so the argument goes, the Kosovar rebels had no better option than to deliberately allow the talks to fail, in effect co-opting the NATO air force into acting on their behalf.

Morally speaking, there was already criticism during the bombing campaign itself that it violated the principle of proportionality since it not only blocked the Serbian army’s access to Kosovo but also damaged civilian infrastructure, including bridges, power stations and industrial plants.

So much for the two sides’ arguments.

Two decades on, what lessons should be learned? There are many, but I will mention just three of them here:

Firstly, NATO’s intervention enabled the Kosovars to achieve self-determination and ended their oppression. However, the peace is fragile at best, and 20 years on, permanent deployment of peacekeeping troops seems unavoidable.

Secondly, it demonstrated that gross violations of minority and human rights are no longer protected by state sovereignty. The subsequent development of the responsibility to protect (R2P) principle was facilitated in part by the Kosovo war. However, this breach of international law also became a reference case for those who believe in the use of armed force, even without a mandate under international law, as a means of asserting their interests, whatever these may be.  Not least, Moscow supported the armed secession of Crimea with reference to the self-determination achieved by Kosovo.

And thirdly, the international community now faces the inevitable question of whether it wishes to maintain the prohibition of the use of force as a universal principle applicable to the powerful and the weak alike, and is capable of providing effective UN-based mechanisms against breaches of the law. Or does it prefer to rely on powerful countries to resolve matters through their own coalitions, if necessary at the expense of existing commitments under international law.

But perhaps this question is anyway moot by now. The US, Russia, China and other powers along with them have long relied on their own military strength to assert their interests, in some cases by agreement among themselves. Were this to continue, it would be the most ominous lesson to be learned for the collective world order since the Kosovo war 20 years ago.