Canada's largest railroads have come to a full stop. Here's what you need to know

Canada’s two largest railroads have ground to a halt after an ongoing labor dispute couldn't be resolved before a deadline. Canadian National and CPKC have shut down all their trains in Canada and halted shipments into the U.S. after failing to reach new agreements with the Teamsters Canada Rail Conference union by a Thursday deadline. The impasse could bring significant economic harm to business and consumers across both countries, which rely on billions of dollars of goods running on trains each month. The big questions are how long the shutdown will last and whether the government will intervene.