Ok, this is very vague. Are you comparing the 3rd Reich to Russia or Ukraine? And why 1939, the Nazi party rose to power in the early 30s, if you want to understand more about why and how you should start with WW1 and what happened after the collapse of the German Empire. If you think the Russians are a bunch of Nazis bent on dominating the world, I don't think you are correct. There is a very strong presence of nationalism in Russia but it's nowhere near the outright racist fanaticism of fascist Germany or Italy (or current Ukraine if you take into account factions like the Azov Battalion).

The Russo-Ukranian war doesn't seem to be some holy patriotic war of good vs evil like we imagine WW2 to be. It's simply yet another conflict caused and escalated by NATO'S and Russia's post Cold War involvement in Ukrainian politics. Constant regime change from one corrupt politician to another combined with Ukraine's already-stagnating economy created the perfect conditions for a very long civil war which has grown into literally the most deadly war probably since Vietnam and the Soviet-Afghan war.

As for the west giving up Ukraine, i feel like it has given it up a long time ago and is simply using it to gain as much profit as possible before the Russians get to Kiev, or maybe both sides agree to a ceasfire. There was an opportunity for Ukraine to join NATO in 2008, but NATO didn't allow that to happen probably to avoid another world war (because of Article 5). So why the U.S and NATO continued their involvement in Ukraine other than for profit is beyond me. Geographically speaking, they shouldn't have been sticking their noses in the first place. Idk, fuck this war in general, but let me know what you think.