Re: Just a FYI
whereas the majority of Crimean residents consider themselves Russian
This is mostly because Russia deported massively Tatars from Crimea. Nowadays we call that an ethnic cleansing:
"Crimean Tatars constituted the majority of Crimea's population from the time of ethnogenesis until the mid-19th century, and the largest ethnic population until the end of the 19th century.Almost immediately after the retaking of Crimea from Axis forces, in May 1944, the USSR State Defense Committee ordered the deportation of all of the Crimean Tatars from Crimea, including the families of Crimean Tatars serving in the Soviet Army."
Also, 75,000 Crimea Tatars died during the 1920s by hunger because of collectivization, when their crops were taken from them and send elsewhere in Russia.
Crimea was "Russified", the dirty way.
If the US invades Cuba, puts every Cuban in a boat, with only Americans citizens in Guantanamo staying, would it be legitimate to accept a pro-US self-determination referendum after that?