It's their country, they can elect a new government, develop as human being etc.
If they don't well, it's on their own. But if they invade other countries and subjugate other nations to this misery then it's a tragedy - just recall that USSR was not a voluntary union and there are still over 100 different nations oppressed in Russia by this senseless system (see for example Russian Federal republics to get the idea).
Russians tend to forget that and try to excuse the misery they have caused to others by claiming that they too suffered. That excuse is invalid.
PS. All of this was actually explained in the following sentence.
