Vladimir Putin currently uses his ideas as justification for Russian moves in the Crimea. Although the situation is not the same, Hitler referenced the same intellect? Whose world shaking words served to justify slicing away chunks of weaker states? Woodrow Wilson.
The end of World War I spelled the end of three multi-national empires, Russia, Austria-Hungary, and the Ottoman Empire. Each one of these states formed around core ethnic groups, Great Russians, Austrians, and Turks. Each group established a powerful state that absorbed surrounding territories peopled by different ethnic, linguistic, and religious groups. Another tie binding the three lay in their belief that they fulfilled the Roman Imperial tradition. This, they believed, gave them the legitimate right to rule others.
The 20th Century challenged that notion and tore it down. Long standing dynasties and loose ties to the Roman Empire no longer mattered. Legitimacy remained a powerful word, but what made a government and its power legitimate? The Bolsheviks substituted class warfare for czarism and kept their empire going. The other two broke up.
Austria-Hungary challenged the West. About 15 different ethnic groups populated the empire and many wanted free of Austro-Hungarian imperial power. Wilson suggested that the peace treaties ending World War I reorder the world on national self-determination. No one, however, defined what that meant. It has remained a staple of US diplomacy ever since, but not without raising puzzling questions?.
Does it mean that each ethnic group has the right to rule itself? Wilson certainly did not think that extended to black Americans and Indian nations.
Does self-determination require democracy?
Does every group have this right, or only groups large enough to form a viable country?
No one knows for sure and we have made it up as we went along. This mostly resulted in good results.
But it also provides justification for National Socialists, white supremacists, and ethnic cleansing. The logic of national self-determination carried to its logical conclusion leads to messy problems, such as Hitler demanding that Czechoslovakia hand over the Sudetenland because it had Germans there. Of course after World War II, to prevent such a thing from happening again, Czechoslovakia, Poland, and other countries expelled every German from fear of this happening again. Serbs and Croats later feared the influence of minority Bosnians in their countries and drove them out.
Crimea is mostly populated by Russians, but is under Ukrainian control according to international law. Putin is, as many have done, appealing to the Wilsonian ideal of national self-determination. The Russian implemented vote in the Crimea chose Russia (whether or not that was a fair vote is highly debatable.)
Putin has put the West in a bind by turning the ideals of Woodrow Wilson and the imposed treaties ending World War I back against it. When addressing Putin, the West will have to deal with the hundred year old specter of the idea of national self-determination as well. Not that it was a bad idea, but a clear definition is way overdue.