A trade war between Canada and the US further ruptures a once-close and durable alliance

The briefing

The collapse of trade talks has fundamentally altered the Canada-U.S. relationship, with the United States imposing 50% tariffs on about $20 billion of Canadian goods. Prime Minister Mark Carney said Canada recognized that America has changed and pledged dollar-for-dollar retaliation beginning Sept. 8 across steel, dairy, appliances and other sectors. Nearly three-quarters of Canada's goods exports go to the U.S., limiting Ottawa's ability to retaliate without significant self-inflicted damage.