I had some relatives who did some stints in the fringes of the USSR. When nationalist violence erupted, one of them commented that national hatred was covered up by cheap slogans about democracy meant for an impressionable west.
As for the powers that be wanting to exploit differences–I could believe that, though if you look at the Soviet central response to crises at the fringe, you will find that there was more incompetence on the part of Gorbachev and others, rather than some sort of coherent attempt to divide and conquer.
This issue was not even brought up in a meeting until half way in or so. That should show that, as far as central governments are concerned, it is not always (at least in the case of Moscow’s government) a coherent plan to divide and rule.