Putin, and Russia in general, are driven by fear, this has been true since WW2. Putin strong-man façade is just that, a façade.
He fears NATO expansion, simple as that. You can argue till end of times that he has no reason to, but reason is not what drives him. This is how, imo, all Russian actions should be looked at, with fear as the driving force. If you can accept that, then russia actions seem more logical, even "justified" (in their mind, before someone comes with the Putin apologist angle, again).
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