Answer :
Final answer:
Protectionist policies in the 1920s and 1930s aimed to protect domestic industries but often resulted in retaliatory responses from other nations, impacting national welfare. The General Agreement on Tariffs and Trade (GATT) was formed to address these issues.
Explanation:
Protectionist policies were implemented during the 1920s and 1930s to shield domestic industries from foreign competition. These policies included tariffs, import quotas, and nontariff barriers. However, retaliatory responses from other nations often led to a reduction in national welfare for all involved, as seen during the Great Depression and the subsequent implementation of organizations like the General Agreement on Tariffs and Trade (GATT).
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