The Federation is not the entire world, there were at least 4 more entities of that level who were distinct, and weren't particularly keen on joining the Federation.
Star Trek: Birth of the Federation captured this quite well in its endings representing Loss, Allied Victory, Domination ( 2/3 of the galaxy controlled) and Total Conquest.
https://www.youtube.com/watch?v=8A8N1N-dREc
Contrast this with the Cardassians: https://www.youtube.com/watch?v=Fy_RbUKsaj0
I too am a trekkie and we could still obtain this vision.
So far only world sanctions have been brought against Russia.
If the Russian people rise up and protest/overthrow their government. It would tell the world that such extreme sanctions are enough to crush a nuclear power and prevent war. That we are indeed post-war. That borders become less important. Instead of war, we take that money and invest in ourselves. We start building tall.
If the Russian people don't do this. It means we are not post-war. It means we haven't broken the cycle. It means in about 2100, the cycle hits again and we have another massive war.