The war won't have happened if the US and some western countries have kept to their promise of not expanding NATO towards Russian borders. And moreover, both Ukraine and Russia are brothers, just in arms. Russia is simply trying to survive hostile NATO policies.
The war won't have happened if Russia didn't invade Ukraine.
Russia wouldn't have invaded Ukraine if the US hadn't gone back on its agreement to not expand Nato, and if they hadn't pushed Ukraine into harming their own people and some Russians as well.
Maybe in BADeckerville.
In the real world that "we won't expand NATO" promise is a fantasy, it doesn't exist. Just like the whole "tHeY aRe CoMiTtIng GeNocIdE!11!!" bullshit.