This is just idiotic equivocation. The difference between Russia and Hitler is that Russia has legitimate national security concerns, for instance, not letting the world's largest military alliance (NATO) which is antogonistic to them, build defense infrastructure along their border, or choke off their ability to have a navy. The Nazis made no attempts to conceal the fact that one of their main national objectives was to invade eastern Europe and create a colonial German empire. Clearly you can see these two things are not the same, right?

If Russia's national objective is to have access to the sea, and doing so means they have to take access from another nation, then no, I don't see how the things are different, except for maybe in magnitude (Hitler just did what Putin is doing, but more. France was building defense infrastructure along its border with Germany too, if you don't recall.) It's the exact same logic though: If you excuse states for invading each other because they have "national security concerns" that involve taking what they want from other nations, the same logic excuses Hitler's actions too. Putin has also made it very clear that one of Russia's goals is to essentially reestablish the soviet union (similar to hitler's feelings about germany's humiliation after WW1), the parallels here are stark.

The US could easily say today that it has a national security concern that it needs Greenland in order to have a good defensive posture against Russia now that the north sea is becoming more navigable. Does that make it morally right to just... invade and take Greenland? I assume that is your position, because it's essentially exactly what Russia is doing. (You don't need to respond if your answer is "Yes". This thread is getting long and if your position is indeed that countries can take what they want if they have "national security concerns", we're far enough apart that there's no reason to continue debating.)