Does this rule apply to drivers entering the U.S. from Canada and Mexico?

This rule applies only to drivers who hold a CDL issued by a state of the U.S. Generally, this would not include drivers from Canada and Mexico. There is a separate rule that addresses Canadian drivers hauling explosives into the U.S. Eventually, all drivers will have to meet threat assessment and eligibility standards that are comparable to the standards that now apply to Hazmat drivers in the U.S.