That's because Hitler kept winning. He militarized the Rhineland in 1936, the allies did nothing. He took over Austria in 1938, the allies did nothing. He occupied Czechoslovakia later the same year, the allies did nothing. With every win, Hitler's popularity increased at home. He's reported to have been quite surprised when the allies finally declared war after Poland.

We have a word for this: https://en.wikipedia.org/wiki/Appeasement

Neville Chamberlain negotiated with Hitler over handing Germany large swaths of Czech territory critical for border defense. The Czechs weren't invited to the conversation.

https://en.wikipedia.org/wiki/Peace_for_our_time

We know how that turned out.

Hitler didn't have nukes and super-sonic missiles -- you cant do to Russia what you would want to do to Hitler.. at least not without a very heavy price..

And when Putin threatens nuclear first strike unless the west removes sanctions, or abandons the baltic republics, what next?

At some point you have to just call their bluff. Earlier is better than later. Putin himself knows that he'll be the first casualty in nuclear war, and I doubt very much that Putin's deputies would go along with a plan that results in the annihilation of the Russian people. He's playing a high-stakes game of chicken.

What does 'call his bluff' translate to in this context? Not take the threat of a nuclear war seriously and engage with Russia militarily anyways as-if the threat didn't exist?

Yes. Use NATO air power to tip the scales in Ukraine. They seem to be doing pretty well by themselves, even just a little help may be enough.

Putin is gambling that the west is too cowardly to fight, and so far he's right. Hitler made the same gamble in 1936.

> Hitler didn't have nukes and super-sonic missiles

While relatively late in the war so it didn't have too much strategic impact, the Nazis literally invented the supersonic missile.

I meant to say 'hypersonic' nuclear icmbs