Sandego.net – At just past midnight on Tuesday, a sweeping set of retaliatory duties on American imports went live across the Canadian border, marking the sharpest escalation yet in a trade dispute that has simmered between the two nations for months. The new levies target roughly $20 billion in US-origin goods and push the combined tariff rate on aluminum and steel imports up to 50 percent — a figure that mirrors what Washington already charges on Canadian metal shipments. Beyond the metals, the package reaches into paper products, construction materials, household appliances, and agricultural commodities, broadening the economic pain felt on both sides of the 4,000-mile border.

The tariffs land at a politically explosive moment. With the US midterm elections roughly two months away, Republican candidates in swing districts and states will now have to field questions about a president whose trade posture is visibly rattling their own party’s base.…