President Trump stops to answer questions from members of the news media as he departs the White House on Nov. 20. (Jabin Botsford/The Washington Post)

President Trump, who once called his attorney general “Mr. Magoo” and referred to the leader of North Korea as “Rocket Man,” has maintained a more respectful nomenclatorial relationship with himself, sometimes going so far as to avoid the pronoun “I” as if it were too informal.

Bill Gates once recalled the president telling him, “Trump hears that you don’t like what Trump is doing,” which is one of many famous examples of what author J.K. Rowling calls “third Trumperson:” the formal means by which Trump speaks of Trump.

At least, those seemed to be the rules until Sunday, when the president addressed himself with a nickname.

“So great that oil prices are falling (thank you President T),” Trump wrote — almost certainly referring to himself, and not the London-based rap musician, @Prez_T (warning explicit content).

Even in a country that has grown somewhat used to the president’s unique styles of communication, be it through third Trumperson or all-caps diplomacy or gibberish tweeted in the middle of the night, the unexpectedly colloquial form of his self-gratitude caused confusion and alarm.

“Trump giving himself the friendly nickname ‘President T’ makes me deeply uncomfortable,” law professor Joyce Alene wrote. “Like he’s trying to cast himself in the role of the good dad all of the neighborhood kids love in a 1950’s TV show.”

And Shawna Thomas of Vice News wrote that she initially assumed Trump was thanking the president of some unknown oil-producing nation. For the record, President Teodoro Obiang Nguema of Equatorial Guinea is the only known “President T” in the Organization of the Petroleum Exporting Countries, but it seems unlikely that Trump had anyone but himself in mind as he penned the tweet from his motorcade on the way to his golf course.

While this is purely speculation, it’s possible that Trump’s new nickname for himself means he’s growing more comfortable with his presidential identity after nearly two years in the White House.

Or, conversely, Trump is drawing some subliminal parallel between himself and his predecessor, whom he has referred to repeatedly as “President O” — though not exactly warmly.

Whatever the intent behind the term, it looks destined to follow other Trump idioms into the cultural lexicon. Within minutes of its coinage, Atlantic editor David Frum was experimenting with modes of sarcasm, while harsher critics of the president wrote “President T” into satirical children’s stories and criminal conspiracy fantasies.

Several others found a precedent in history for what President T did this weekend. They recalled a famous athlete and entertainer from the late 20th century, named Laurence Tureaud.

If the name doesn’t ring a bell, it’s because Tureaud later renamed himself Mr. T. Perhaps the name “Trump” will one day be similarly forgotten.

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