If they lost control of "regions" there's a lot more to it than sneaky Russians infiltrating into the Ukraine.
Honestly, I’m not convinced of that.
I think there is a lot of manipulated unrest and Russian agents on the ground in the Eastern Ukraine.
Yeah, that's what puts me closer to the second premise.
I think MOST of the folk in those regions want to be with mother Russia.
Hell, Russia built Odessa from the ground up and has controlled the Crimea for over 2 centuries.