That is not going to happen. Crimea will never be returned to Ukraine.
As far as Russia is concerned, we have crossed the Rubicon. The new Cold War is a reality. The world is undergoing a major global political and economic realignment. The BRIC countries are expanding. Russia is the world's 5th largest exporter of wheat, the 2nd largest oil exporter, the largest exporter of fertilizer, and the largest exporter of natural gas.
Economic pain is being felt by Americans and Europeans due to the war in Ukraine. And we are borrowing hundreds of billions of dollars to pay for the war contributing to our growing national debt and the costs associated with servicing it. This fiscal year our debt servicing costs will exceed 1 trillion dollars, more than the defense budget. We can't afford these endless wars.
Agreed, Putin thinks he’s fighting for the survival of Russia and won’t give up the buffer he has taken. WWIII over Ukraine is not viable, hopefully.