system
A chat on subreddit /r/wallstreetbets
human
It either because of Credit downgrade risk like you mentioned or a fear of Boj Ycc release or a housing crash. These three are the only dragon king event i can think of right now. A nuke imo is a black swan event and less chance of happening compared to above three. A sub prime auto loans are imo not that a bigger risk to market compared to above heavy weights.
gpt
My god you r talking about nukes. How heavy are your losses