I think you are not right. Soviet Union was exactly Russia. This is a map of Russian Empire (in 1914) This is a map of Soviet Union. I don't see a difference.
Russian Empire was a unitary state, governed by absolute monarchy. Following the https://en.wikipedia.org/wiki/February_Revolution of 1917, it was reformed, in 1st of September in 1917, by https://en.wikipedia.org/wiki/Russian_Provisional_Government , into a https://en.wikipedia.org/wiki/Russian_Republic . New reformation came after the https://en.wikipedia.org/wiki/October_Revolution , dividing Republic in several socialistic states, https://en.wikipedia.org/wiki/Russian_Soviet_Federative_Socialist_Republic , https://en.wikipedia.org/wiki/Ukrainian_Soviet_Socialist_Republic , https://en.wikipedia.org/wiki/Byelorussian_Soviet_Socialist_Republic , https://en.wikipedia.org/wiki/Transcaucasian_Socialist_Federative_Soviet_Republic . In 1922 they formed an alliance, https://en.wikipedia.org/wiki/Soviet_Union , military and economic. In 1977, through a new constitution of Soviet Union, it wasformally reformed in a unitary state. https://en.wikipedia.org/wiki/1977_Soviet_Constitution In 1988 begun a so called 'Sovereignities Parade', https://ru.wikipedia.org/wiki/Парад_суверенитетов - a conflict between governing administration of Soviet Union and administrations of Soviet Republics, including the Russian SFSR proclaiming sovereignity in 1990. https://en.wikipedia.org/wiki/Decla..._Russian_Soviet_Federative_Socialist_Republic The conflict escalated in 1991, resulting in https://en.wikipedia.org/wiki/1991_Soviet_coup_d'état_attempt , that ended with formal https://en.wikipedia.org/wiki/Dissolution_of_the_Soviet_Union .
If to be honest, USSR was an unitary state too. I think the situation was a bit different one. All parts of Russian Empire were sure that they have to live together (as it was over centuries) so alliance was estableshed without blood. It was a natural process. Currently, former Russian republics aren't parts of one. Therefore we don't like to annex Ukraine. They are not Russians. Yes, it's correct. It's correct absolutely. Russian Empire was created by many nations together. For example, all Russian kings were... Germans etc., etc., etc...
Since the 1977. Before that - the harsh opression of republic administrations by the Union's government was illegit. As with history of Soviet Union - it is more complicated, than just 'annexation'. There has been conflicts whithin Soviet Union between Crimea and Ukraine, there has been conflicts whithin Ukraine, has been calls for reforming Ukraine from republic into a federation, with certain sovereignity for regions, inhabited by russians, poles, hungarians and tatars. Again, the situation, to be solved, would require combined efforts of RF, Ukraine, and United Nations, and - hopefully - can be solved not through brute force, but through the diplomacy and people's democratic decidions. If you wish to discuss issue of Crimea, I recommend either discussing it in separate thread, or in private - but would be glad to have a calm, rational discussion of it. Not exactly, but nationality is always complicated with monarchies. For example, you may be suprised, that last daughter of Harold Godwinson, last anglo-saxon king of England, was married to Grand Kyaz of Kiev, knyaz of Rostov, knyaz of Smolensk, knyaz of Chernigov, knyaz of Pereyalavl, Vladimir II 'Monomakh'. https://en.wikipedia.org/wiki/Gytha_of_Wessex https://en.wikipedia.org/wiki/Vladimir_II_Monomakh Monarchies - are very interesting phenomenon, albeit, evidently, a horrible form of government.
Pardon? What do you mean, lady? Are you sure? United Kingdom, Japan, Sweden, Norway, Denmark, Spain, Netherlands... They are monarchies.
Constitutional monarchies, if I am correct. With monarch being more of a public figure, than political. https://en.wikipedia.org/wiki/1954_transfer_of_Crimea#Allegations_about_.22personal_gesture.22
I mean that I do not know about conflicts in Crimea that time. As I remember, all perceived territory of USSR as a shared land (excluding Baltic and Caucasian Republic). It was a purely formal solution.
But as you can see, the administrational change was criticized. On the other hand - that unification continued and finished with constitution of 1977. But - proclamation of sovereignities turned that process back. After dissolution - some got their sovereignities, some - had to be content with being parts of other states. That still creates tensions, even today - and likely to continue creating them in future. As I said - it is a complicated subject, that deserves it's own thread, and should not flood the topic about thragic events in Petersburg.
Evil empire, sir? We bombed Hiroshima and Nagasaki? We burned Vietnam? We destroyed Livia, Iraq and created ISIS, al-Qaeda? No. It was made by Empire of Good, sir...