Donald Trump threatened Canada with 25% tariffs and even quipped about a merger of the two nations. The North American neighbors have strong economic links, so what could be the impact of a trade dispute?

Justin Trudeau chose Jan. 6, a day fraught with significance for Americans, to announce he will depart from the Canadian Office of the Prime Minister. He did so after last year’s visit to President-elect Donald Trump ’s Mar-a-Lago club spectacularly misfired.

Donald Trump’s increasingly strident approach to relations with Canada is provoking fear about the potential consequences north of the border and questions about just how serious the U.S. president-elect actually is.