From what we've witnessed in the last few years, it's rather obvious to me that the big bad folk are working together. It's even likely that mutually assured destruction played a role on this. In a "Let's fully crush the plebs together if we can't crush each other" kind of way. I don't dig the idea that any of them would fancy living underground for decades or more, even if they can count on "winning" the exchange in the end. Or fancy losing their precious and growing assets.
There's also a rapidly spreading theory - including from people whose opinions I generally respect - that Nukes aren't real. I don't know, nor currently have the energy to research this. So much has proved to be insane lies. Could this also be one?
More war will happen, perhaps even something resembling WW3. At least for a while, it's going to be theater war with real casualties. Maybe if the (not so) hidden global empire crumbles, we can go back to fighting each other honorably. Preferably with Rhomphaia and Pilum.
But for know imagine war coming to your doorstep. It's likely pretty much anywhere. With martial law and health emergency combined. Tech oppression advancing, fascists cheerleading and most people even more terrified. It might even include a Nuke or two for WOW effect. Or "Nuke" if you don't believe in those. I fear all those, but not a global nuclear apocalypse.