Where do you draw the line? Since you say this is purely dependent on Putin's subjective perception, and since you can't read his thoughts, would the logical consequence be that we need to just let him do unopposed whatever he wants to, out of fear that the smallest grievance could result in nuclear armageddon? This, to me, seems what imperialism apologists are arguing for. Ignore the war of aggression, ignore the genocide, rape and murder of civilians, sacrifice Ukraine to protect Putin's ego, and just pray that his greed stops at that and that he won't continue given another opportunity.