1929-1945: Library of Congress
The widespread prosperity of the 1920s ended abruptly with the stock market crash in October 1929 and the great economic depression that followed. The depression threatened people's jobs, savings, and even their homes and farms. At the depths of the depression, over one-quarter of the American workforce was out of work. For many Americans, these were hard times.
See the Great Depression, from Wikipedia:
In the United States, the Great Depression began with the Wall Street Crash of October 1929 and then spread worldwide. The nadir came in 1931–1933, and recovery came in 1940. The stock market crash marked the beginning of a decade of high unemployment, poverty, low profits, deflation, plunging farm incomes, and lost opportunities for economic growth as well as for personal advancement. Altogether, there was a general loss of confidence in the economic future.
See the Dust Bowl, from Wikipedia:
The Dust Bowl was the result of a period of severe dust storms that greatly damaged the ecology and agriculture of the American and Canadian prairies during the 1930s. The phenomenon was caused by a combination of natural factors (severe drought) and human-made factors: a failure to apply dryland farming methods to prevent wind erosion, most notably the destruction of the natural topsoil by settlers in the region. The drought came in three waves: 1934, 1936, and 1939–1940, but some regions of the High Plains experienced drought conditions for as long as eight years.
See the New Deal, from Wikipedia:
The New Deal was a series of programs, public work projects, financial reforms, and regulations enacted by President Franklin D. Roosevelt in the United States between 1933 and 1938 to rescue the U.S. from the Great Depression. It was widely believed that the depression was caused by the inherent market instability and that government intervention was necessary to rationalize and stabilize the economy.
See World War II, from Wikipedia:
World War II or the Second World War (1 September 1939 – 2 September 1945) was a global conflict between two coalitions: the Allies and the Axis powers. Nearly all the world's countries—including all the great powers—participated, with many investing all available economic, industrial, and scientific capabilities in pursuit of total war, blurring the distinction between military and civilian resources. Tanks and aircraft played major roles, with the latter enabling the strategic bombing of population centres and delivery of the only two nuclear weapons ever used in war. World War II was the deadliest conflict in history, resulting in 70 to 85 million fatalities, more than half of which were civilians. Millions died in genocides, including the Holocaust of European Jews, and by massacres, starvation, and disease. Following the Allied powers' victory, Germany, Austria, Japan, and Korea were occupied, and war crimes tribunals were conducted against German and Japanese leaders.