This is true. But it’s more of a pricing power problem. The US can no more rid itself of the dependency on Canadian heavy oil than Canada could on exporting to the US. We’re bound together on that front, and it’s why oil has been exempt from tariffs.

If Canada had the ability to sell that oil on the global market, we’d get a better price for it (if you only have one customer you can sell to, you have little pricing power). Western Canada Select trades at a discount to WTI.

US refineries are built for a mix of heavy and light oil and that’s not practical to change. The US can’t just replace Canada with its own oil or imports from elsewhere.

What about Venezuela? Another potential source of heavy oil? It would take decades of investment and development to bring that up to the point where it produces an extra 4 million barrels a day for export. With the uncertain political environment there, it’s unclear where that would come from.