Section 338 of the Tariff Act gives Trump an easy – but untested – way to impose new levies

The provision was long ago superseded by trade legislation, but Congress never explicitly repealed it Stainless steel coils at a factory in Montreal. U.S. President Donald Trump's latest tariffs are meant to punish Canada for retaliating against his previous tariffs on autos, steel and aluminum.Christopher Katsarov/The Canadian Press