President Donald Trump announced he’s ending “all trade negotiations” with Canada because of a television ad sponsored by one of its provinces that used the words of former President Ronald Reagan to criticize U.S. tariffs — prompting the province’s leader to later pull the ad.The post on Trump’s social media site Thursday night ratcheted up tensions with the U.S.’s northern neighbor after Canadian Prime Minister Mark Carney said he plans to double his country’s exports to countries outside the U.S. because ...