To understand why Russia has invaded the Ukrainian region of Crimea now, one should recall why it didn’t do so 20 years ago.

In 1991—the year the USSR collapsed—an attempt by Serbian-majority regions to secede from the newly independent Croatia led to one of the worst bloodsheds in Europe’s recent history. It was definitely on the minds of Russian, Ukrainian and Belarusian leaders when they convened in December 1991 and decided to dissolve the USSR peacefully, respecting the existing administrative borders between former Soviet republics. They prevented a war that would have made conflicts in the Balkans look like pub brawl—just imagine if ex-Yugoslav armies had gotten a hold of world’s biggest arsenal of conventional, chemical, and nuclear weapons.

It was a very difficult decision for Russia, particularly because it left millions of ethnic Russians outside Russia proper, fending for themselves in a new and extremely unsafe world. Ukraine, hammered into its present shape by Lenin, Stalin and Khrushchev (who enlarged it by adding vast swathes of Russia proper and Poland), was a particular cause of concern. But Yeltsin clearly didn’t want to be seen as a nuclear Milosevic—and we should be grateful for that. That’s how Crimea, with its ethnic Russian majority, ended up in Ukraine without being given any real chance for self-determination.

It’s not only a sense of responsibility that prompted Yeltsin to make this decision. The idea of giving independence to various parts of the Soviet empire was indeed popular in Russia at the time. In January 1991, an 800,000-strong rally in Moscow—possibly the biggest in Russian history—demanded the right for Baltic countries to be independent. Russians weren’t averse to Ukrainian independence, either. It was the year of big hopes and immense enthusiasm that contrasts so sharply with extreme cynicism, apathy, and suicidal fatalism that’s engulfing Russia now.

So how did we wind up with Russia invading Ukraine 23 years later?