Trump Administration Tariff Actions: Frequently Asked Questions [Updated December 15, 2020] [open pdf - 2MB]
From the Introduction: "The U.S. Constitution grants Congress the sole authority to regulate foreign commerce and therefore impose tariffs, but through various trade laws, Congress has delegated authority to the President to modify tariffs and other trade restrictions under certain circumstances. [...] The Trump Administration's tariff actions raise a number of issues for Congress and have been the focus of congressional debate. Such issues include the effect of the tariffs on U.S. economic activity, such as increases in the price of imported goods, affecting both U.S. consumers and producers, as well as diminished competitiveness of U.S. exports in foreign markets as a result of tariff retaliation. The tariff actions, their frequent modifications, and the exemption application process have also created uncertainty for U.S. businesses. In addition, questions over whether the Trump Administration's tariff actions adhere to congressional intent for the use of delegated tariff authority, in part due to broadly defined statutory criteria, have led to debate in Congress over potential legislative reforms. Congress may also consider how these tariff actions affect the multilateral trading system and the U.S. role and leadership in that system, U.S. bilateral trade relations, and whether tariff increases are an appropriate tool in the negotiation of broader trade reforms."
CRS Report for Congress, R45529
Congressional Research Service: https://crsreports.congress.gov/