What started after the Crimean War was concluded after World War I and the Russian Revolutions. Countries were created after the default of the Austrian-Hungarian Empire and the transformation of the Ottoman Empire into modern Turkey. Drawn up borders and created countries started to exist in the former borders of fallen empires without respecting the desires of the population and ethnic and cultural backgrounds. Yugoslavia and Czechoslovakia are examples which were created in 1918 and less than a century later stopped to exist.
Yugoslavia ceased to exist by the hand of violence, a brutal civil war between those members seeking independence and those opposing it and murderous attempts of land grabbing even between those seeking to depart from Yugoslavia. At the height of the civil war, the West intervened with even more brutal violence against the violent Serbian efforts to maintain Yugoslavia as a state or at least extend the territory of Serbia. Both Serbia and Bosnia paid a high price. The first for their struggle against the break up of Yugoslavia, the later for their independence from Yugoslavia and the ruling Serbian power base.Croatia, victim and perpetrator in its attempts to free itself from Yugoslavian and Serbian dominance and at the same time pushing to extend its borders into Bosnian territory, played a dubious role and in the end gained independence into the republic it is today. When Kosovo developed its desire for unilateral declaration of independence, the West stretched all its might and military capabilities to ensure this would take place as requested by the majority of the now independent republic.
Czechoslovakia showed the world another path to break the unwanted union which was created in the vacuum at the beginning of the 20th Century. Negotiations as equal partners, acting and reacting to every hurdle on the path of independence, the former Republic was dismantled into 2 proud and independent republics with a strong bond. Not a bullet was fired! This all was possible, good and bad, in the vacuum which was created by the default of the Soviet Union.
During this process of default, former Soviet Republics had the opportunity and took that opportunity. Ukraine and Belarus, founding members of the United Nations, were greeted into their independence by Western powers. Other former Soviet Republics like Georgia and Uzbekistan followed the same path and declared independence under their own constitutional powers. The Baltic states, disputed Soviet States since they were absorbed under the German-Russian pact, were supported in their strive for independence by the same Western powers and obtained this independence. All implemented treaties, preliminary and ratified constitutions came into force and Western powers and the Russian Federation cooperated to ensure the transitions were done peaceful, ensuring that legislation and will of the people were aligned.
One former Soviet Republic was deprived of this process: Crimea!