‘Trump Biggest Risk To Canada’: Mark Carney On Reciprocal Tariffs From US Canadian Prime Minister Mark Carney said that the 'biggest risk' to the nation's economy is United States President Donald Trump. This comes after the US imposed reciprocal tariffs on several countries, which affected trade across the globe. The US and Canada have been at loggerheads over certain issues, including tariffs, the smuggling of fentanyl drugs, and Trump's demand to make Canada the 51st state of the United States.