Tariff
In contrast, in economic theory tariffs are viewed as a primary element in international trade with the function of the tariff being to influence the flow of trade by lowering or raising the price of targeted goods to create what amounts to an artificial competitive advantage. When tariffs are viewed and used in this fashion, they are addressing the country's and the competitors' respective economic healths in terms of maximizing or minimizing revenue flow rather than in terms of the ability to generate and maintain a competitive advantage which is the source of the revenue. As a result, the impact of the tariffs on the economic health of the country are at best minimal but often are counter-productive.
Tariff in United States history
The "Trump tariffs" were imposed by executive order (not by act of Congress) during the presidency of Donald Trump as part of his economic policy. In January 2018, Trump imposed tariffs on solar panels and washing machines of 30 to 50 percent. He soon imposed tariffs on steel (25%) and aluminum (10%) from most countries. On June 1, 2018, this was extended on the European Union, Canada, and Mexico. The only countries which remain exempted from the steel and aluminum tariffs are Australia and Argentina. Separately, on July 6, the Trump administration set a tariff of 25% on 818 categories of goods imported from China worth $50 billion.