The problem of Putin..
There is a good saying that might be relevant here. "The rhinoceros has poor eyesight, but with its weight, this is not his problem". 
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Who's there to decide
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People who live there decide what they want to be and no-one else.Who's there to decide
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And the people of Donetsk People's Republic and the Luhansk People's Republic decided to break away form the abusive Ukraine in 2014.
Like a divorce when the abused partner finally had enough and goes the own way, married no more.
It is a Family Feud and nothing to do with the rest of the world.
Do you really believe this war is about Donetsk and Luhansk?
Even Putin isn't clear about that. First it was about Crimea, then those separatist republics, then about Nazis, then about Ukraine joining Nato, now it's about demilitarization.
Do these "people" want Ukraine to become defenseless vassal state of Russia?
And one more thing, if it's all about what the people want, maybe one day "the people" will want you to live in their country and speak their language and if you don't, you'll get denazified.