Autonomous governing body(a regional parliament, I believe) has been running Crimea under the Ukrainian constitution, prior to Putin’s invasion. I don’t need to be Ukrainian to know that.
Now, if Putin were Stalin, I would share your concerns. I think the whole thing has been over-sensationalized by our “media” to make Obama look like a great statesman and protector of freedom and Kerry a great diplomat. I wish they would had held him for ransom when he went to Kiev.