Hoover's wartime service made him a favorite of many progressives, and he unsuccessfully sought the Republican nomination in the 1920 presidential election.
Republican President Warren G. Harding appointed Hoover as Secretary of Commerce in 1920, and he continued to serve under President Calvin Coolidge after Harding died in 1923. Hoover was an unusually active and visible Cabinet member, becoming known as "Secretary of Commerce and Under-Secretary of all other departments". He was influential in the development of air travel and radio. He led the federal response to the Great Mississippi Flood of 1927. Hoover won the Republican nomination in the 1928 presidential election and defeated Democratic candidate Al Smith in a landslide. In 1929 Hoover assumed the presidency during a period of widespread economic stability. However, during his first year in office, the stock market crashed, signaling the onset of the Great Depression. The Great Depression dominated Hoover's presidency, and he responded by pursuing a series of economic policies in an attempt to lift the economy. Hoover scapegoated Mexicans for the Depression, instituting policies and sponsoring programs of repatriation and deportation to Mexico.
