In an infinitely multipolar and equal world, you'd be correct. That is not the world we live in. Countries are of unequal size, population, climate and natural resources.

Without making a long comment I'll make a short one. Russia's position can in many ways be simplified to this: We went into Ukraine because the US and NATO went into Ukraine, after helping violently overthrow the neutral and democratically elected government of Ukraine in 2014. We'll get out after you get out, and there is some guarantee that you'll stay out.

I'm not in favor of Russia's invasion, but it is hard to argue with that position.