U.S. President Donald Trump said Monday that 25 per cent across-the-board tariffs on imports from Canada and Mexico, with a lower 10 per cent levy on Canadian energy, will start Tuesday, tipping the continent into a trade war.

The tariffs U.S. President Donald Trump has threatened to impose on Canada tomorrow are clearly an economic danger, but are they also an existential threat? Trump in recent weeks has repeatedly suggested Canada should become the 51st state and threatened to use “economic force” to join the two countries together.