This is an endless war, where the Bolsheviks overthrew the Russian Empire and founded the Soviet Union, the Soviet Union collapsed and the Russian Federation emerged, until Putin's ambition to reunite the countries of the former Soviet Union under Russia. We can only hope that Putin's ambitions will not trigger a third world war which will cause massive casualties and huge economic losses.
Putin sees the future and plans to prevent things like war. If he wants war, he would have crossed the borders already.
Back in 2014, Putin already saw the threat when Ukraine people started a coup and install a president that is not Russian friendly such as Zelensky.
We couldn't really say Ukraine has democracy if we look at what this Zelensky did after he won. For one, he shut down the TV channels and imprison his counterpart.
So couldn't really say just as Biden says that he protect Democracy because it's BS.
This is when Russia also claims Crimea which is once theirs in the first place but there is a trade between the two countries which they've settled. Putin will always have plans to protect Russia because he had seen over and over in the entire world how countries fall and are being occupied by the US military. Countless of them. He already sees it that in time US military might also be in their backyard (Ukraine)
He defends his country, I don't think he will claim back the Soviets when the world is fully new and countries are equipped with nukes. I don't think Putin would like to rule a land filled with ashes. Besides China is much stronger economically and in terms of military forces.