The covered list, and the excluded one
From Wednesday, duties of up to 50 percent apply to about 20 billion dollars of Canadian goods: hockey sticks, some clothing, wines, some dairy products, and building materials such as cement and plywood. Energy products, potash, fish and critical minerals are excluded. Prime Minister Mark Carney, who called the negotiations very delicate and intense, has until that morning to move the line.[1]
Set that against the flow it sits in. Canada was the third-largest source of American imports in 2025, with more than 380 billion dollars of goods crossing the border, so the covered slice is a narrow cut of the traffic. Trade Representative Jamieson Greer named why it was cut at all: two countries in the world have retaliated against American trade measures, the People's Republic of China and Canada. The duty is addressed to a negotiating posture, not to a shortage.[1]
Where the leverage stops
The exclusions map the dependency. Potash goes into American fertiliser, energy products into American fuel, critical minerals into everything downstream of them; a duty on those raises a price at home before it ever reaches a negotiator in Ottawa. What stayed on the covered list — sticks, shirts, wine, cement, plywood — has other suppliers, so the tariff can be paid by switching orders. It is a measure built to be felt on a date, and its mark on any supply chain is fainter. The carve-outs may equally be there to hold down American fuel and fertiliser prices, which would leave the same goods outside the list for a reason that has nothing to do with substitution.[1]
The enforcement point is untested. Section 338 of the Tariff Act of 1930 has never been invoked by a president, and legal challenges are all but certain, so an importer clearing a covered shipment on Thursday is pricing a rate and a lawsuit at the same time. This column wrote earlier that the transshipment report named 40 economies but left the origin decision at the border unwritten; the Canadian action runs the other way, setting a rate and a date with no origin test of its own, while Ottawa says the step violates the North American trade agreement. If the duty takes effect without a deal, the figure worth watching is the monthly import value of the covered categories through October: a fall means orders moved, a flat line at a higher price means the duty was absorbed.[1], [2]