The Edenic pre-fall
The book doesn't start right with the Great Depression: instead, the book contains an insightful depiction of life before the Crash and the Great Depression. This is shown to be like an Edenic state of innocence before the Fall of Man, because the nation seemed to be flourishing. New credit systems offered new capitalistic opportunity to consumers who could not have purchased what they wanted on real money alone. Then, the credit system breaks down, and the innocence is lost in a moment of panic and horror.
The Crash
The Crash is a symbol of changing fates, because one day, the nation is rather pleased, using the credit system to make purchases that they wouldn't have been able to buy with real capitol; then suddenly, the market plummets, and everyone is left with the same question: how far can this Crash plummet? The answer is way lower and more horrifying than anyone had predicted. The market Crash shows the true nature of the economy as a fragile construct of confidence.
Panic en masse
The runs on banks offers a living symbol of hysteria, because people panicked en masse. They tried to withdraw their money just to discover that the banks didn't have money to give them, because the banks invest in the economy, and the economy crashed. The panic isn't something that only businesses and corporations felt; it was felt by individual people on every level of society.
The Depression as a sign of hopelessness
The Great Depression is portrayed as an archetypal moment in history that can be used as a reference of human hopelessness. Unfortunately, not everyone survived. There were suicides precipitated by sudden losses of enormous wealth, hopelessness in homes riddled by poverty, and instead of looking for work and finding it, people were scavenging for food trying to survive at all costs. This is the nation's rock bottom in some ways.
Paranoia and lessons learned
The exit narrative is quite a different allegory than the edenic lead-up to the downfall. The nation exits the Great Depression still riddled by economic shell-shock. The people struggle to find hope in the future, because they were most of them so blindsided by the Great Depression that it becomes impossible to ignore the abstract threat of future chaos. They are paranoid by the Depression, making the Depression a kind of trauma that the whole nation shared.
