How did the Great Depression affect protective tariffs in the United States? By raising exports, tariffs were beneficial to the economy.

A tariff is a tax on goods imported into a country. It was thought that high tariffs would force people in the home country to buy items made in that nation, instead of buying items made in other countries and then imported. Before the Great Depression, the United States had an incredibly protectionist trading system, particularly when the Republicans had power in congress. Two senators, Smoot and Hawley, created a bill and eventually it was passed to create the Smoot-Hawley tariff, the largest tariff in the history of the United States.

Once this happened, other countries increased their tariff barriers in retaliation, which resulted in a sharp decline in global trade, which heightened the effects of the Great Depression once the stock market crashed.

Arguing about whether tariffs are "good" or "bad" is a little simplistic but high tariffs are definitely a bad thing and stifle international trade.