Prime Minister Justin Trudeau highlighted the close ties between Canada and the U.S. while visiting an international union conference in Philadelphia, Pa., on Tuesday. "The links between the Canadian and the American economy are so deep and indeed getting deeper over the past year our trade numbers have reached higher levels than any time before,” Trudeau said. “We will be there to defend effectively against unfair or punitive tariffs on Canadians because we know it'll be a lose-lose on both sides of the border.”