Smoot-Hawley Tariff Act (1930)
Congress raised US tariffs on nearly 900 imported goods in June 1930. Trading partners retaliated with their own duties, and US exports fell by roughly half within two years.
World trade collapsed, deepening the Great Depression. More than 25 countries responded with counter-tariffs.
The episode discredited protectionist tariffs for decades and helped build postwar support for trade agreements like the General Agreement on Tariffs and Trade.
Shows how tit-for-tat tariff escalation between trading partners can spiral into broad economic damage.
