Serbia, Spain, and other states opposed to the independence of Kosovo argue that its unilateral declaration of statehood is illegal under international law. (Prior posts here, here, and here; map credit.)
Those supporting Kosovo’s independence, including the United States, don’t seem to disagree. Rather than arguing that Kosovo’s declaration can be reconciled with principles of territorial integrity, they contend that Kosovo is “sui generis” and therefore “does not set a precedent.” In other words, no, it isn’t legal, but not to worry, it won’t happen again.
Certainly Kosovo is in some ways unique. Those making the sui generis argument point to the break-up of Yugoslavia, Security Council Resolution 1244 (1999), and the long period of UN administration as distinguishing features. Basing a claim to independence on UN intervention is in some ways reassuring, as any nascent polity receiving such intervention must have considerable international support. It is in other ways disturbing, suggesting that the decisive factor in determining the legitimacy of claims to sovereignty is not the freely expressed will of the people but the will of the international community -- not self-determination but UN-determination.
In any event, there are a lot of independence-seekers in the world who are hoping that they too are sui generis, and it won’t be long before they begin to put the question to the test. The New York Times reports that South Ossetia and Abkhazia, independence-seeking regions in Georgia, have indicated that they will ask for recognition from Russia, which has long supported them, based on the Kosovo (non-)precedent. (map credit)