"Canada does a lot of trade with the much larger U.S. economy...2.6 million Canadians, 13 percent of the work force, are employed directly or indirectly producing goods exported to the United States. So U.S. tariffs will impose a huge shock on Canada’s economy.
It's not clear how much Carney can or will do to mitigate that shock. But he has no alternative to going elbows up: There’s no way to satisfy Trump’s demands."