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,

President Trump's threat of tariffs against Mexico and Canada has been realized with the U.S. imposing a 25% tariff on nearly all goods imported from those two countries. An additional 10% tariff has also been added to the existing measures against China,