I fundamentally disagree with all of these.
The premise from Kennan is that we must cuddle Russia like a child. Why should we favour Russias infantile wishes over Poland and the Baltics, who are now EU members and have benefited tremendously from the west receiving them welcomingly?
And ask those countries, they for sure
would have said, then and now, that this was always going to happen. Because it has before. The neighbours have Russia have a far more intimate understanding of how Russian aggression works because they have been continously exposed to it for centuries now. They, like these quoted figures, warned of what was coming, but inevitably so, and without the callous cost considerations of Russian appeasement.
Kissinger, classically, talks about this whole thing as if only the great powers have agency and dismisses the will of the ukrainean people.
Mearsheimer makes the same fallacy. "the west is leading Ukraine down a path." sorry, but what utterly patronising bullshit. Colonialism in drag. I won't bother addressing the rest. All of it is imperialist apologism.
It is not the responsibility of the west to cuddle the pre-modern militant imperialism of an intransigent nation. And it is certainly not the responsibility of the west to sacrifice on that altar the wishes for freedom, democratic open societies and secure sovereignty of countries in the European sphere, simply because they have the misfortune of neighbouring Russia.
These analysts have already been proven wrong. It has proven to be a great decision from 'the west' to welcome Poland and the Baltics with open arms when they reached westward with alacrity. I dread to think of how central and Eastern Europe would look like today if we had just turned away and said 'they are Russia's sphere of influence.'
If there is something to be learned from 21st century geo politics, it is that the west ought to be vigilantly supportive of countries that desire democracy, open societies and sovereignty to do so. It should be clear by now that the non democratic greater powers will not find their path to our way of thinking through trade, prosperity and good will, as neo liberals believed. On the contrary, they will subvert democracy wherever convenient for them. The responsibility of the democratic block in the 21st century is to support democracy against such assaults.
Today that is Ukraine. In ten years, it will likely be Taiwan.