I'm not at all confident Russia could conquer Poland though even if it's left to fight alone (together with the Baltic states). It spends ~65% more on its military than Ukraine, has full access to western tech and way less internal problems (good luck finding any region in poland where > 0.x% of the population would want to join Russia). Even if Russia 'defeats' the Ukrainian military (which I don't think is at all certain) what is Putin's next step? Any regime they install in Ukraine would require enormous resources to maintain power and I don't see how can Russia afford that, at best they can bite off some regions in eastern Ukraine.

Also most Russian don't seem to be even close to being as enthusiastic as the majority of Nazi Germans were when their tanks rolled into Paris. Russians seem to be mostly apathetic, they don't really support the war but also are not willing to actually stand up and do anything about it. That might change if there is not quick victory/large amounts of civilians start being killed/sanctions actually start working.

That plus in case of full occupation by Russian forces the partisan attacks will bleed occupation forces for years to come

Once the coffins start to come back to mother Russia domestic support for occupation will plummet even further locally in Russia.

Even in USSR, with censorship and active repression USSR was still bringing back afghan war coffins in the dead of the night.

You speak with such impunity on matters that are clearly not for the average folk.

The situations in 1939 and 2022 are only similar insofar as we are talking about the same country. Everything else is different.

Wasn’t the NATO founded in 1949? And doesn’t this imply we haven’t lived thru this, as the conditions of NATO did not yet apply in 1939?

Even still, I'm not sure the lack of political will in France/Britain after Poland was attacked was the reason it fell. The allies they just did not feel like they had capability to start and offensive against Germany and expected Poland to hold out much longer than it did.

Czechoslovakia would probably be a much better example (however NATO did not exactly agree to recognize the annexation of Crimea and the Donbas just to appease Putin).

I think times have changed quite a bit. Poland was always thrown to the dogs before, but now it's a pretty decently respected country. It also has economic value to the EU as a whole.

it is not just Poland. Now it is Poland, Romania, Lithuania, Latvia, Estonia and Czech Republic. They are all NATO and are all "between" Germany and Russia.