From the Document: "The trade practices of U.S. trading partners and the U.S. trade deficit are a focus of the Trump Administration. Citing these and other concerns, the President has imposed tariff increases under three U.S. laws: (1) Section 201 of the Trade Act of 1974 (Table 1) on U.S. imports of washing machines and solar products; (2) Section 232 of the Trade Expansion Act of 1962 (Table 2) on U.S. imports of steel and aluminum, and potentially motor vehicles/parts and titanium sponge (the President decided not to impose tariffs on uranium imports, after an investigation); and (3) Section 301 of the Trade Act of 1974 (Table 3) on U.S. imports from China. Congress delegated aspects of its constitutional authority to regulate foreign commerce to the President through these trade laws."
CRS Insight, IN10943
Congressional Research Service: https://crsreports.congress.gov/