The Soviet union obsessed over World war 2 for 2 reasons- because 20 million of its people were killed, and because it was the only time in its godforsaken blood-soaked history it had the moral high ground.
Communism never had a moral high ground
They held no moral high ground; plenty of those 20 million died fighting for the Axis (Ukrainians welcomed the Nazis as liberators, and that only went sour when Soviets slipped behind the lines to sabotage that deal by spurring German reprisals against civilians - they admitted it after the wall came down). They had already invaded the Baltic states and half of Poland before Hitler attacked them (they had arranged those invasions/seizures with Hitler beforehand), and in the 1930s had already killed millions of their own people (hence the Ukrainian support for the Axis). Other countries with nothing but positive feelings towards the Western Allies participated in Operation Barbarossa because of Soviet threats to their freedom BEFORE the war; that is why resistance was so stiff even after it became clear the war was lost.
The Soviets held no moral high ground; we lowered our own image by supporting them - and Eastern Europeans in particular don’t mind saying so to this day.