I know you're mostly joking, but it's not going to happen. There aren't enough powerful countries on the theoretical opposition side to sustain a WW3 engagement.

There are only a few consequential military powers today that can seriously attempt to fight a major war outside their own borders while simultaneously enduring opposition: US, Russia, China, Germany, France, UK. All the next tier powers down from that can be trivially crippled, locked down to their own territory and prevented from substantially joining the battle. IE there can be no WW3 until or unless the world changes a lot.

Nothing says WWIII would have to be sustained. It's been generally expected for the past several decades that it would last a day or less.

Yes, I'm mostly joking. But sadly enough, rather darkly :(

And I misspoke in saying "WWIII". What I meant was a nuclear exchange between the US, Russia and their allies. That's almost happened more times than most people realize. The Cuban Missile Crisis did pretty much happen in public. What would that have looked like on Twitter?

To add to that, you need a large and consistent oil supply to sustain a war on that scale and it is no accident that the North American, South American and Middle Eastern oil regions are effectively all under US control.

Not Russia, though. But anyway, I misspoke. Not a protracted war.