Good point, it's offensive realism, not defensive realism. Here's how this war fits into Mearsheimer's framework: great powers have a certain amount of power.

Good point, it's offensive realism, not defensive realism. Here's how this war fits into Mearsheimer's framework: great powers have a certain amount of power. There are 3 great powers today, the US, China and Russia. The power of a nation depends on its population and GDP, and lots of other things as well. Russia's population is going down, its GDP is just a fraction of China's or America's. So, their great power standing is on the decline. A conquest of Ukraine, if speedy and decisive, would convince all the other former Soviet Republics to submit to Russia voluntarily, maybe with the exception of the Baltic republics which are part of NATO. If Putin reincorporates the Russian Empire, the population doubles overnight, a feat not achieved even by Bismark. The GDP also increases, although not that much. Still, under such a scenario, Russia under Putin would achieve a huge leap in great power standing. It would probably still not be number 1, but it could be number 2, because, despite having much lower population and GDP than China, it would have fresh war experience. Given that this fits so well in Mearsheimer's framework, it's obvious that all of Putin's rhetoric about the NATO transgressions is just that, rhetoric.