President Donald Trump has justified tariffs on Canadian imports by citing a flood of smuggled fentanyl. But nearly all of the powerful opioid is smuggled from Mexico.

U.S. tariffs on Canada have put experts at odds over how appropriate the action was, particularly given the unaddressed demand side of the fentanyl epidemic.

U.S. President Donald Trump has made numerous tariff threats since returning to office on January 20, ranging from a universal duty on imports to targeted tariffs on specific sectors or countries, in a bid to get others to meet his policy demands.