Current barriers on imports into Canada from the US affect dairy, wine, telecommunications like TV, cable, and broadcasting, and even software and “cloud” data storage.
“The CRTC also requires that 35 percent of popular musical selections broadcast on the radio qualify as “Canadian” under a Canadian government-determined point system.”
“This requirement precludes U.S.-based “cloud” computing suppliers from participating in the procurement process, unless they replicate data storage and processing facilities in Canada.”
In contrast, there are very few barriers to trade with Mexico.
(Edited to add the link to information on Mexico.)