The Globe and Mail reports in its Thursday edition that two major American private-sector unions representing manufacturing workers have strongly opposed President Donald Trump's new tariffs on Canadian goods and urged the White House to reverse its decision. The Globe's Vanmala Subramaniam writes that Roxanne Brown, president of the United Steelworkers (USW), and Brian Bryant, president of the International Association of Machinists, warn that President Trump's new 50-per-cent tariffs on select Canadian products, effective Aug. 19, are "unfair trade" and will further strain U.S.-Canada relations. Both unions wrote to U.S. Trade Representative Jamieson Greer on Tuesday, urging the White House to reconsider using Section 338 of the Tariff Act to impose levies and restore a more stable U.S.-Canada trade relationship. The USW has often publicly supported Mr. Trump's trade policies. If new tariffs do take effect on Aug. 19, USW workers in the forestry sector -- representing 14,000 jobs -- will be most affected, given that the tariffs extend to plywood, particleboard, veneer and some paper goods. "Many of these jobs are in remote communities, so holding that job is everything to them," said USW Canada's Marty Warren.