The Globe and Mail reports in its Wednesday, April 2, edition that President Donald Trump aims to impose new 25-per-cent tariffs on imported automobiles to encourage automakers to build more factories in America. The Globe's Matthew McClaren writes that Mr. Trump has also vowed to permanently shut down Canada's auto manufacturing sector. Due to Mr. Trump's actions, the mix of U.S. and foreign content in vehicles sold in the U.S. has become crucial. On March 26, the White House announced 25-per-cent tariffs, which may not apply to the entire vehicle value. For vehicles under the United States-Mexico-Canada Agreement, the U.S. Secretary of Commerce can impose the tariff only on non-U.S. content. However, if U.S. Customs and Border Protection finds discrepancies in the declared non-U.S. content value, the full tariff applies. The agency has not provided guidance on required documentation for importers. Greig Mordue, an engineering professor at McMaster University, said questions of national content bedevilled automakers and government officials even when the stakes were far lower. Mr. Trump's proclamation asserted that free-trade agreements, including USMCA, have not yielded sufficient positive outcomes.