President Donald Trump’s blanket 25% tariffs on Mexico and Canada took effect on Tuesday, an extraordinary action aimed at bringing America’s top trading partners to heel. But it threatens to weaken the North American economy,

Growth expectations for the U.S. economy are falling as China and Canada announce their next move in the tit-for-tat trade spat with the White House.

President Trump imposed hefty tariffs on the United States’ largest trading partners on Tuesday, roiling global relations and sending shock waves through industries that depend on trade.