Before Donald Trump became president, he had a long history of tearing out pages from magazines (or printing out offending articles), scrawling some nonsense in Sharpie, and mailing it to the party he believed had wronged him. But while most people in his current position probably would have dropped the habit—which feels not dissimilar to a kidnapper’s M.O. of cutting and pasting letters that spell “If you ever want to see your dog again...”—this particular president has been using his Zodiac Killer–inspired method of communicating to conduct matters of U.S. diplomacy.

Axios reports that back in May 2017, Trump tore off the cover of Businessweek—which featured a picture of Canadian prime minister Justin Trudeau and the headline “The Anti-Trump”—and wrote, in silver Sharpie, something to the effect of “Looking good! Hope it’s not true!” In spite of the concerns of some staffers, who were stricken with the crazy notion this was an inappropriate way to communicate with a foreign leader, the White House then sent the missive to the Canadian Embassy in Washington, where the Canadian ambassador thought he was being pranked. Per Axios, he called the White House to check, and was sadly told that the note was real.

Alarmingly, that wasn’t the last time the president of the United States chose to communicate with the prime minister of Canada in such a fashion:

Months later, on Dec. 8, 2017, President Trump falsely told a rally crowd in Pensacola, Florida, that the U.S. has a trade deficit with Canada. Around that same time, Trump also mailed Trudeau a document purporting to show that the U.S. had a trade deficit with Canada, according to a source with direct knowledge. Trump wrote in Sharpie on the document: “Not good!!” or something to that effect, the source recalled. Trump’s document only mentioned America’s deficit in the trade of goods and ignored its surplus in services (the two combined would give the U.S. its overall surplus).

At that point, Trudeau seemingly realized that the only way to respond to Trump was to come down to his level, the one in which heads of government use sentence fragments and emojis to communicate: