Putin retains the cynical cold-war world mentality he was steeped in as a KBG spy.
It is true that parts of Ukraine might have been incorporated into Russia, but they weren't because of decisions made by the USSR, and later validated by Ukranians.
History saw Ukraine become a sovereign Nation, with all the attendant rights of any independent Nation.
The annexation of Crimea got a pass, because when Krushchev had transferred it to Ukraine in 1954, it was virtually an administrative change, under the monolithic USSR, and the reason for him doing it remains obscure.
Putin's actions are out of time, and I believe the West will eventually gather its courage and repel his military adventurism which is firmly rooted in the past.
Western democracies are slow to act, initially, but I think the need for democracies to directly fight for democracy against authoritarianism will see the West directly fight Putin's invasion of Ukraine.
