Every country in the world, including the United States, maintains high tariffs on at least a handful of products for which domestic producers are thought to be vulnerable to foreign competition. This so-called tariff protection is typically imposed early in an industry’s life or at moments of weakness or decline, when the threat from more efficient foreign producers is thought to be particularly severe. Once imposed, tariff protection is very difficult to remove, because the enterprises and workers who benefit from it work hard to keep it in place.