I never thought they'd go full doomsday growing up, though as history teaches us, that had elements of luck to it such that there's gotta be timelines where they did, but I'll be honest I have kinda been amazed someone somewhere hasn't blown off a nuke being morons so a merciful Providence be thanked for the overtime work there.
I mean as a species we sure do produce some thickies, esp. lately, and give them access to atomic weaponry, so miracles are likely involved. :)