In June 1991, Croatia declared independence from Yugoslavia. Germany and the Vatican stood against the world in recognizing the new state. The United States, Britain and France were dead against it. British officials warned at the time, “Take one look at the map of Yugoslavia, and you realize that, with the sole exception of Slovenia, the nationalities and religions are so enmeshed that there is no peaceful way of breaking Yugoslavia up …. [T]o support independence for the republics is to sanction continuous civil war.”
Military and diplomatic historian R. Gerald Hughes noted in The Postwar Legacy of Appeasement: British Foreign Policy Since 1945, “In truth, while fearing the further fragmentation of the former Yugoslavia, the British were also alarmed at the possible resurrection of the specter of a German-dominated Mitteleuropa.”
Britain and France fought against the German recognition in the UN, only to acquiesce to German pressure. The war that had already begun in Croatia ripped across the rest of Yugoslavia, and the region descended into chaos—exactly as the British had predicted.
Why was Germany so keen to break up Yugoslavia? It gave Europe the opportunity to expand in the Balkans. But it was also a chance to push back at Russia. Relations between Yugoslavia and Russia had soured during the Cold War, largely because Russia’s geographic position had changed. Russia controlled Europe all the way to East Germany—it had much less need for a forward base in the Balkans. For the Serbs, Russia’s advance had transformed them from a distant power, which could be of some help, to a nearby threat.
Once the Iron Curtain fell, Yugoslavia once again became a valuable potential ally to Russia. Such an alliance would help Russia project power into Europe much more aggressively. Imagine, for example, the Ukraine crisis—except with an intact Yugoslavia as a Russian ally: It would have been Italy and Austria on the front line, rather than Poland and the Baltics. (Of course, if Germany had not broken up Yugoslavia, there might not have been a Ukraine crisis.)
It is not difficult to see, then, why Europe was so intent on fracturing Yugoslavia. In the turmoil of the fall of the Soviet Union, the newly unified Germany had the opportunity to neuter this potential Russian ally and took it. Later, also against Russian wishes, Kosovo was broken away from Serbia.
In doing so, however, Germany took a risk. In forcibly splitting up Yugoslavia and then prying Kosovo away from Serbia, it broke the most important rule in postwar Europe: no unilateral redrawing of European borders. That precedent has been exploited by Putin in Crimea and could be exploited again.
That rule was followed for almost 50 years for good reason. Once you start questioning Europe’s borders, it leads you to some very dark places. And it was exactly those questions Putin raised in Crimea—and is raising again in the Balkans.