Hoover signs Smoot-Hawley Tariff Act, raising tariffs to record highs and triggering retaliatory trade war

President Hoover signed the Smoot-Hawley Tariff Act, raising average tariff rates to approximately 45-50 percent on over 20,000 imported goods — the highest sustained tariff level in American history. Canada, Britain, France, and Germany immediately retaliated with counter-tariffs on American exports. U.S. imports fell from $4.4 billion in 1929 to $1.3 billion in 1932; exports fell from $5.2 billion to $1.6 billion. Economists widely credit the tariff war with deepening the Great Depression.