U.S. economy protectionist Smoot–Hawley Tariff Act
The decline in the U.S. economy was the factor that pulled down most other countries at first; then, internal weaknesses or strengths in each country made conditions worse or better. Frantic attempts by individual countries to shore up their economies through protectionist policies – such as the 1930 U.S. Smoot–Hawley Tariff Act and retaliatory tariffs in other countries – exacerbated the collapse in global trade, contributing to the depression. By 1933, the economic decline pushed world trade to one third of its level compared to four years earlier.
