Canada is the biggest supplier of heavy crude to American refiners, exporting it at a rate of close to 4 million barrels daily, which makes it the biggest exporter of crude oil to the U.S. in general. Mexican crude oil exports north of the border are much smaller, at less than half a million barrels daily, but they still comprise the second-largest share of foreign oil in U.S. refiners’ mix. That fact may have played a role in Trump’s willingness to negotiate new trade deals quickly before the tariffs kick in and retaliation begins.
