Except for crap of the word "enslave", yes it was obligation. And first of all, the USSR had obligations to its people. Together with Hitler, Romanians, Hungarians, Poles, Croats, Slovaks etc. came to enslave the soviet people.
You enslaved Eastern Europe to protect Russians.
Now NATO protects Eastern Europeans from Russians.
The USSR declared them fraternal countries...
Well, that makes enslavement more palatable.
They were "enslaved", can only be said by an idiot.
Defending enslavement can only be done by an idiot.
despite the promises made to Gorbachev that NATO will not advance to the east,
Free countries deciding to join NATO, just awful!!
Trust Russia not to invade.