I am open to recognizing Crimea as part of Russia, if another referendum is held with a reasonable campaign time frame and conducted by the Crimea government.
I think the biggest issue with this, as with doing the same in Kosovo, is that these territories are now dominated by people who would certainly vote to confirm the constitutional change. The Ukrainian citizens that were living in Crimea at the time of the Russian offensive may, and probably would, have made a substantial difference to the outcome of a referendum held at that time - as compared to the result of a referendum held now.
