Instability and downfall
Perhaps the most instructive theme of the book is that states of instability only come crashing down. This book details one of the most heartbreaking, horrifying moments in American history. Part of the disturbing nature is that it was unpredicted by the masses. The economy seemed healthy, but was actually a house of cards. On a national and even global scale, the Depression is like a tragic downfall where the "hubris" was the invention of the credit system.
The American Dream
The American Dream is critically tied to this book's core meaning, because it is the narrative that shapes the narrative of each person's daily life in the nation. What happens, therefore, when someone who wants to better themselves cannot find a job because the entire economy has collapse? That pops the bubble of the Dream, so that the person is left with the full weight of existential dread. The Depression is not just economic; it is also felt depression in the lives of people who cannot find a path out of the horror of absolute poverty and hopelessness.
Public opinion and health
Through the book, the reader sees that the public is its own organism with a kind of health system. Instead of public opinion being something surface level, the book portrays it as deeply substantial and important. The policies of the New Deal are created to improve public opinion to a stable place, like a homeostasis. This theme resonates throughout the whole book, so that the Great Depression isn't just a historical fact; it is a real experience that people felt.
