President Trump is escalating his trade war with Canada, doubling down on a 95-year-old law to potentially ban Canadian dairy products, most alcoholic beverages, and motorcycles.
"It seemed inevitable that Trump would need to have the last word," Capital Economics said in a note, "and the administration has responded by leaning on another part of Section 338."
That's a provision from the Tariff Act of 1930, which was signed by President Herbert Hoover. Trump has cited that authority for his latest actions, though the law is often cited as the literal textbook example of tariffs gone wrong.
More widely known as the Smoot-Hawley Tariff Act, it raised effective US tariff rates in the early 1930s into the double digits, leading to a trade war with Canada and others and a fall in imports, which economists agree worsened the Great Depression a few years later.
But beyond the inconvenient historical parallel — Trump has often recoiled at being compared to Hoover — a more pressing concern for the president will likely be whether the authority is legal.