Yes, the Russians want the Kurds as a counterbalance to Turkey coming into Syria.
The Turks do not want the Kurds to have their own state, as many reside in Turkey as well. There are also many Kurds in neighboring Iraq.
The Russians intend to be a player in the Middle East, and they want to keep the warm water access they have already secured in Syria, whether Assad agrees or not.
At this point, Assad will do what the Russians tell him to do, because otherwise he would have been strung up by now.
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Reminds me of the movie Goodfellas that scene where the bar owner needs protection from crazy Tommie so he makes Paulie a partner for protection.
Assad is the bar owner in this scene and Don Paulie is Putin.
https://www.youtube.com/watch?v=3XGAmPRxV48