Short answers, pulled from the story.
Protectionism is the economic policy of restricting imports from other countries through tariffs on imported goods, import quotas, and other government regulations. Proponents say it shields domestic producers, businesses, and workers from foreign competitors and raises government revenue, while opponents say it reduces trade and raises the cost of imported goods for consumers.
There is a broad consensus among economists that protectionism has a negative effect on economic growth and economic welfare, while free trade and the reduction of trade barriers have a positive effect. The principle of comparative advantage holds that free trade creates more jobs than it destroys, and economist Stephen P. Magee claims the benefits of free trade outweigh the losses by as much as 100 to 1.
Tariffs and import quotas are the most common protectionist policies, a tariff being an excise tax on imported goods and a quota being a legal limit on import volume. Other tools include protecting patents and technical knowledge, restricting foreign direct investment, administrative barriers, anti-dumping legislation, direct and export subsidies, exchange rate control, and campaigns like Buy American.
According to Douglas Irwin, the Smoot-Hawley Tariff of 1930 was not the primary cause of the Great Depression but contributed to its severity by provoking international retaliation and reducing global trade. The act raised the average tariff on dutiable imports from about 40 percent to 47 percent, and price deflation pushed the effective rate to nearly 60 percent by 1932.
TRIPS, the WTO agreement on intellectual property negotiated between 1989 and 1990, has been criticized for limiting governments' ability to allow generic producers, most visibly over AIDS drugs in Africa. The Doha Declaration of November 2001 clarified that TRIPS should not prevent states from addressing public health crises and allowed for compulsory licenses.
According to Douglas Irwin, US tariff history divides into a revenue era from 1790 to 1860, when duties supplied about 90 percent of federal receipts, a restriction era from 1861 to 1933 that protected domestic industry, and a reciprocity era from 1934 to 2016 focused on negotiating trade agreements. The eras were separated by two shocks, the Civil War and the Great Depression.
Protectionism has been attributed as a major cause of war, with proponents citing the mercantilist warfare of 17th and 18th century Europe and Frederic Bastiat's slogan that when goods cannot cross borders, armies will. Archaeologist Lawrence H. Keeley counters in War Before Civilization that disputes between trading partners escalate to war more often than disputes between nations that trade little.