Russia is internationally recognized as the legal successor state to the Soviet Union and assumed the Soviet Union's rights and obligations. So I am not sure how you dont see the connection. Today, Putin regimes tries to revive the Soviet past, conceals the past crimes and commits new crimes against own people and people in other countries, like Ukraine and Syria.

Following the Molotov–Ribbentrop Pact, Stalin collaborated with Hitler and helped to boost his regime militarily and economically. Together they invaded Poland and other countries killing together innocent. No Ukrainians did such atrocities despite being attacked by both evil forces.