But the facts of the matter are even simpler than that! 1) Some #NEVERTRUMPERS with big bucks want to make Trump look bad 2)some investors/hedgies didn't think that Trump's tax cuts would work, so they went short 3)and the BIG one...the damned programed trading kicked in and is now running the DOW and the CBOE messes.
There was absolutely NOTHING out there, that most could see, to crash the market in '87! IT WAS THE EARLY PROGRAMMED TRADING THAT SET THAT ONE OFF! Luckily, there were still more than enough warm bodies on the floors of the exchanges, to "save" and "right" the markets, within that same week.
Bubble/shmubble....that "crash", back in '08, just as McCain rose to 3 or 4 points over Obama in the latest poll? If you don't believe that there was a "fiddle" and an extra thumb on programmed trading re that one, I have an old CBOE floor badge to sell ya...cheap! :-)
I have an easier, simpler theory than that about the 2008 crash. It coincided with higher fuel prices. Fuel is one of the prime movers of the US economy. Fuel prices would have been much easier to manipulate than the market, and have a more direct and fundamental effect.