Honey, you can literally Google: "John Mearscheimer Russia Ukraine". People *have* pointed you in the right direction. We're trying, but you've gotta try too.
I did and it says here that John Mearscheimer thinks that Ukraine and Russia should share a snickers because “you’re not you when you’re hungry.” Context is everything and I could go read possibly 100 links and not know what “go google John Mearscheimer Russia Ukraine” means. I got an answer from someone who didn’t want to play this stupid “you go guess and hopefully figure out what we mean” nonsense game.
Here is also a rebuttal of John Mearsheimer. https://vatniksoup.com/en/soups/250/
Thats not a rebuttal, its a smear piece with very little attention to the contents of his arguments