President Donald Trump, a self-declared “Tariff Man,” has made the threat and use of tariffs one of the chief operating mechanisms of his administration’s foreign and economic policies. He has said on numerous occasions that he “likes tariffs” and that they will help make America great again. The use of protective tariffs had fallen into disfavor following World War II, but President Trump has singlehandedly brought them back into play again. In this regard, he has compared himself to William McKinley, a president who never saw a tariff he did not like. Trump has leaned toward a form of an “America First” isolationism. He is skeptical of the value of U.S. participation in international organization...