Mr. Trump’s decision to impose tariffs on metals is not new. In his first term, the president levied tariffs on foreign steel and aluminum globally, angering allies like Mexico, Canada and the European Union. He ultimately rolled back some of those barriers on Canada and Mexico when they signed a revised trade agreement with the United States.

U.S. President Donald Trump signed an order that would impose 25% tariffs on steel and aluminum imports. Perhaps unsurprisingly, the biggest winner of the trade tariffs is likely to be the U.S. "At the start,