I also thought that gang violence question was rhetorical. :P
Your prediction is "backed up" by disasters that happened in a time far too different from the modern day, and/or catastrophes that don't hold a candle to nuking the entire world. I would say the only one you could barely compare in terms of the scale would be the bubonic plague, but those have nothing in common other than a huge amount of deaths.
Oh, and the Holocaust too, but it's pretty hard to compare massive genocide in pseudo-secrecy to blatant nuclear world's end in anything else but, again, death count.