Why did the end of world war 1 harm the US economy?

The end of World War I led to a rapid demobilization of U.S. troops and a shift from wartime production to peacetime, causing widespread unemployment and economic disruption. Additionally, the abrupt end of government contracts for military supplies created a surplus of goods and a decline in industrial output. This transition, coupled with inflation and a speculative Stock Market, contributed to economic instability, ultimately leading to the recession of 1920-1921.