Another chapter in decades-long battle over one of the most important trade routes in North America is set to unfold this week. Prime Minister Mark Carney says the new Canadian-built Gordie Howe bridge, connecting Windsor and Detroit, will open this week unless the U.S. president blocks it. Donald Trump claims the U.S. was never fully compensated for the bridge even though the Canadian government financed it. Mackenzie Gray reports on the political headwinds it still faces.