And, as for eating and killing children, it's easy: starvation. If you're hungry enough you'll eat children. All it takes is a supply chain disruption, much more likely than nuclear war even.
So why not eat the children now? It's gonna happen anyway.
It's true that I am jumping the gun here. We don't need an apocalypse for AI to suck ass. It sucks ass right now and is causing massive problems. We should probably focus on that.