Who has the right to be independent?

Ever since the invention of nationalism we have been squabbling over what is a nation and which peoples get to be independent. The United States began with a separatist revolution, and since then we have taken every sort of position on whether various "nations" should be independent states:

• In 1812, we tried to liberate French Canada from British rule.
• We supported the independence movements in Latin America from Mexico to Chile.
• In 1861-1865, we fought a war over whether the South could separate from the North, but meanwhile the unionists helped West Virginia separate from Virginia.
• In 1903 we helped Panama separate from Colombia because Colombia was not very supportive of our canal project.
• After Wold War I we supported the creation of independent states in Poland, the Baltic, Czechoslovakia, and Yugoslavia, but opposed the separation of Slovakia from the Czechs, Croatia from Serbia and the Flemings from Belgium.
• After World War II we joined the British in insisting that the Karen people remain part of Burma; they have been fighting for independence ever since.
• In 1967 we opposed the independence of Biafra from Nigeria; our reason for this was that since all the national boundaries in Africa are arbitrary and cruel, questioning one would open up all of them to question. But then just recently we supported the independence of South Sudan, which immediately fell apart into factional fighting.
• We supported the independence of East Timor from Indonesia but opposed the separatist movement in Aceh.
• In the 1990s we supported the independence of Croatia from Yugoslavia, but then refused to allow the Serbian-speaking part of Croatia to secede and join Serbia. (This one really bugged me.)
• Then we supported the independence of Kosovo from Serbia even though some of our closest allies opposed it and the International Court of Justice ruled that it was illegal. 
• We supported the independence of Georgia from the Soviet Union, but not of Abkhazia from Georgia.
• We refused to support the independence of Chechnya from Russia and turned a blind eye while the Russians laid waste to the country in the course of reconquering it.

So I think it is pretty much ridiculous for us to take a strong stand about the possible independence of Crimea.

I do understand that crazy things are happening in Ukraine, and that the Crimea is occupied by Russian troops, which is hardly the right circumstance for a referendum. But where is it written that Crimea must remain part of Ukraine for all time? They have only been part of Ukraine since 1954. The great NY Times map above shows that Crimea is almost entirely Russian speaking, and voted very heavily for the President just driven out of Kiev.