Churchill has seen this

"in the United States, extraordinary optimism sustained an orgy of speculation. Books were written to prove that economic crisis was a phase which expanding business organization and science had at last mastered. "We are apparently finished and done with economic cycles as we have known them," said the president of the New York Stock Exchange in September. But in October a sudden and violent tempest swept over Wall Street. The intervention of the most powerful agencies failed to stem the tide of panic sales. A group of leading banks constituted a million dollar pool to maintain and stabilize the market. All was vain. The whole wealth so swiftly gathered in the paper values of previous years, vanished. The prosperity of millions of American homes had grown upon a gigantic structure of inflated credit now suddenly proved phantom. Apart from the nationwide speculation in shares, which even the most famous banks had encouraged by easy loans. A vast system of purchase by installment of houses, furniture, cars, and numberless kinds of household conveniences and indulgences had grown up. All now fell together."

This was written by Winston Churchill in the book The Second World War: Milestones to Disaster.