Not Europe but a few Baltic states are feasible. No one says they can hold it, but Putin has his own reasons so we should not think we can conclude on future Russian actions based on what we consider reasonable - e.g. no one predicted that a war on Ukraine was likely as it seemed to be completely irrational and self-defeating.
If nothing else, war has been many times convenient to keep regimes in power (see Bush post 9/11 for an obvious example). Putin might want to strengthen his case. See absurd discussions / push for a "Republic of Narva" as an example cause belli.
If nothing else, war has been many times convenient to keep regimes in power (see Bush post 9/11 for an obvious example). Putin might want to strengthen his case. See absurd discussions / push for a "Republic of Narva" as an example cause belli.