President Trump imposed 50 percent Section 338 tariffs on targeted Canadian imports in July 2026, citing discrimination against U.S. exports in autos, dairy, and alcohol, with those duties taking effect after trade talks collapsed in August. Canada responded with retaliatory duties on roughly $27.6 billion in U.S. goods, including doubled steel and aluminum rates effective September 2026. The administration countered in September by converting some duties into import bans on Canadian alcohol and dairy while adjusting the covered product list. These steps have sustained an escalatory cycle rather than any tariff reductions, with both sides maintaining pressure on USMCA-compliant trade flows. Future bilateral negotiations or executive adjustments remain the primary variables that could alter the trajectory.