The number of people who'd be easily willing to just murder a bunch of people for an invented reason is much greater than elsewhere.
Americans can get 'nationalist' but they are absolutely not like that, beyond a smaller group, Americans are by default positive and gregarious.
I believe Russia's dark past, their permanent oppression, total lack of hope for something to change makes them amenable to this. Basically, institutionalized cynicism.
I believe that even Putin himself, former counter espionage is the most cynical it gets, like Machiavellian without recognizing that 'hope and prosperity' are actually legitimate things. He sees everything as a cynical game of power. The Americans 'can't possibly be acting in good faith' because 'there is no such thing as good faith' - but even worse - not even knowing what 'good faith' is because he's never been exposed to it. 'People who smile are fools, unserious, they can't be competent!' etc. not able to just recognize a basic common joy.
The contrast between attitudes and motivations by Ukrainians these days is just unbelievable, which is interesting because despite historical similarities, it's almost as if 'modern Ukrainian identity' is formed out of the hope that arises when coming out of that rubble. Even regular Ukrainians, farmers seem to be on a different wavelength.