President Donald Trump pulled out of trade talks with Canada Thursday night, furious over what he called a “fake’’ television ad from Ontario’s provincial government that quoted former U.S.

By the weekend, negotiations between Washington and Ottawa were frozen, and President Donald Trump had imposed fresh tariffs.

The 1987 radio address by the former U.S. President Ronald Reagan at the centre of a new U.S.-Canada row was a defence of free but fair trade in which he explained his decision to put duties on Japanese goods in a trade dispute.

Reagan saw tariffs as a last resort. For Trump, they are the first step to force scores of countries into high-pressure negotiations.