"We are reaping the natural fruit of the orgy of speculation in which millions of people have indulged. It was inevitable, because of the tremendous increase in the number of stockholders in recent years, that the number of sellers would be greater than ever when the boom ended and selling took the place of buying."

The quote above was made in reference to an event that would most directly inspire

The Smoot-Hawley Tariff Act
The 18th Amendment
Prohibition
The Volstead Act