Following the passage of America’s Smoot-Hawley Tariff in 1930, countries raised trade barriers in a tit-for-tat frenzy, with no rules to constrain their behavior. The architects of the postwar global order therefore established the General Agreement on Tariffs and Trade (GATT) in 1947, which embodied such rules – as does the World Trade Organization, which absorbed and expanded the GATT in 1995.