Do you understand price flexibility? If the world price is $68/bbl, how does Canada sell it at $80? They don’t, Canada eats the tariff and pays America.
No, no, no, no, no, and NO.
Marathon in Galveston cannot swap out light, sweet Texas crude for the gloopy stuff that comes out of Canada’s Athabasca range.
But beyond that, on what planet does a producer subsidize a consumer at a loss?? US refiners have the option of shutting down production, but short of that they’re SOOL.
Depends on the extraction cost.