Explaining the Fine Points of AI Apocalypse

It's been bugging me that I failed to completely fill in my thoughts in my posting The AI That Eradicates Life Will Be Like a Fervid Red Sox Fan.

[Fandom is] not about a team. It's not even about baseball. It's just a pose that solidified. This is how we do: Strike a pose, select an intensity level, and allow it to bake in. All for shits-and-giggles. A computer could easily do the same. "Always favor Red Sox to non-Red-Sox." Done! Parameter set!

But if an AI capriciously and arbitrarily decides, just like a human sports fan, that Yankees fans suck, it is not at all difficult to imagine nuclear bombs going off moments later.

I heard the potential objection (I'm cursed with always hearing the potential objection) - "Wait, how does that actually happen?" - but thought I might let readers work through it themselves. But this not being 1884, asking folks to read long, wordy, thoughtful, focused writing AND declining to pre-chew every last morsel is a deal-breaker.

So I've added (just below that part, in italics) an explanation as to how an AI could escalate to blazing nukes, for your soothing enjoyment. Have a look, if you're interested.