Experts tell us
that Russia is particularly worried that the strong divisions
in Ukraine over NATO membership, with much of the
ethnic-Russian community against membership, could lead to a
major split, involving violence or at worst, civil war. In
that eventuality, Russia would have to decide whether to intervene; a decision Russia does not want to have to face.
https://wikileaks.org/plusd/cables/08MOSCOW265_a.html
2008 Classified Cable describing potential future
Experts tell us that Russia is particularly worried that the strong divisions in Ukraine over NATO membership, with much of the ethnic-Russian community against membership, could lead to a major split, involving violence or at worst, civil war. In that eventuality, Russia would have to decide whether to intervene; a decision Russia does not want to have to face.