Like, if they launch on Ukraine. The nuke will go off on its target. Do you feel like the rest of the world who is anxiously watching what is happening will sit back and do nothing?
There's some game theory here I hope we don't get to test, but you could rationalize why the West wouldn't retaliate with more nuclear bombs despite MAD (or rather because of). For instance, not walking into a nuclear apocalypse.
>That is basically what they are doing now, sit back and do nothing.
Ukraine never joined any military alliances. They never took the risk of needing to defend someone else, but in so doing meant they never got us to back them. That was their decision.
>Just some economics sanctions...
You don't end a war by adding to it. These sanctions will destroy the russian people. The russian people are innocent in all of this. If the Russian people do not rise up and overthrow their government. Then the sanctions were not inconveniencing enough for them to do that. Through their actions proving their collaboration.
If we can end this war by sanctions, crushing a nuclear power. The fear of global sanctions will be a message to every single person on Earth that war is no longer possible. We will evolve as the human species to be warless. This will be amazing.
The Russian people have a decision in front of them.
It's doubtful that Americans would choose to turn their cities to glass because Putin launched a single rocket in a non-US trajectory. I just don't see that happening.
Any launch regardless of trajectory will be considered act of war against the world. There will be no warning shots here.