The truth was, foreign commerce was taking away American jobs in the farm sector as early as 1922, the Smoot Hawley Tariff got passed June of 1930 was addressing those problems.
Add to that, the housing boom had started to fizzle in 1928 after the hurricane in Sept 1928 that wrecked Florida's real estate market.
These were major items, but the individual investor had no idea of his perspective to all of these irrelevant events.
Here is a quote from a book on the depression; Quoted from “The Thirties America and the Great Depression” c1967,by Fon W. Boardman, Jr. page 26
Perhaps most ominous of all was the increase in bank failures. In 1929, 659 American banks had failed: in 1930 the number rose to 1,352, and in 1931 to 2,294. Just before Christmas, 1930, the Bank of the United States in New York City collapsed. It had 400,000 depositors, many of them recent immigrants, and its failure, the worst in the country’s history, affected a third of all the people of the city. A bank panic in the Middle South closed 129 banks. As usual, people began to withdraw their money and it is estimated that by 1931 they had taken $1,000,000,000 from the care of the bankers and had hidden it away in everything from safe deposit boxes to old mattresses. And just at the time when the people were losing jobs and money, states and other governmental units imposed new taxes to make up for declining revenues from other sources. Thus the depression was chiefly responsible for the introduction of the sales tax, Kentucky being the first state to have one, in 1930. Other states and cities followed suit.
Whats the prognosis? I believe that there are still two years to go before there is a consensus of opinions that we are in a major depression. Its not that we cannot read the road signs. Everyone in the lifeboat must feel the burden of doom before the perspective of reality hits home and survival mode kicks in.
The people that survive this up and coming event, will be marching to a different drummer.