The problem with Mearshimer's ideas is we have to accept Russia's demands and the system they are organized around. Can one country demand its neighbor's do things because they have an army? Why should we accept what a dictator like Putin wants? Who cares if he made his demands in public or how long he has been making his demands? The question is are his demands reasonable? Was Russia imminently threatened with destruction? Of course not. If we accept Russia can demand what it wants because might is right and Ukraine is in their sphere of influence then we logically have to accept all sorts of attacks by large countries against smaller countries. Do we really want to live in that world? If might is right shouldn't the West say to Russia "We are 10X stronger than you, do what we say or we will crush you. Ukraine is ours." Would Russia be at fault for provoking the West in this case? Mearshimer doesn't make a lot of sense unless you are some sort of fascist Russian dictator like Putin or Neville Chamberlain 2.0.