system
A chat on subreddit /r/wallstreetbets
human
they won't be able to print enough money for the buy orders lol IF china were to announce something on US bonds...the amount of selling that would happen on the stock market if that news is real would be biblical. 
  
 multi level circuit breakers would kick in I bet.  
  
 Because that kind of news means trade war is happening.

gpt
Does the bond market have circuit breakers?  Doesn't the fed just buys the excess?