From an article by Robert Cullen in the July issue of The Atlantic:

The nation and its rights are slippery concepts to define and adjudicate, particularly in the Soviet Union. When Soviet people talk of their respective nations, they usually speak of a homogeneous group united by blood, religion, language, and a homeland. The reality is much messier. . . .

The Russians are the dominant nationality in the U.S.S.R., but this has been true for only a few centuries, roughly since the reign of Peter the Great. In the various eras before Peter's time the resent-day Ukraine was the metropolitan power of the Slavic world. Poland occupied Moscow, Lithuania briefly stretched from the Baltic to the Black Sea and Genghis Khan and his hordes swept out of Central Asia and subjugated a large part of Russia and the Ukraine.

As a result of this primordial competition for land and power, some nations have actually perished. The Scythians, the Pechenegs and others fought the Russians on even terms for centuries but exist now only in some shards of pottery and rusted weaponry. Others, like the Chuvash, the Cheremiss and the Komi, have almost but not quite disappeared as distinct peoples on territory now part of Russia. Lithuania and Latvia adapted to the hegemony of Poles or Russians or Germans or Swedes and survived to lay their present claims to independence.

This untidy Darwinian history ensures that the game of national assertion in the Soviet Union has an almost unlimited number of players and potential conflicts, and that no rule or set of rules can be applied to the region to produce a settlement that will be satisfactory -- or even fair -- to everyone.