ok let's make a deal mr realist professor: stalin's "mistake" (the tatar genocide/force deportations from crimea) in exchange for khrushchev's mistake (giving the ethnically cleansed crimea to ukraine).
and after we bring back those tatars (we have to figure out how to make descendants out of people who were killed before they could create any, but that's small things) we let them have it.
while we're at it, i think russia should demand we give them back alaska or else because that was a big mistake.
history would be so different if mistakes could be taken back.