Carlos Barria / Reuters

In Donald Trump’s bizarre, meandering 81-minute press conference on Wednesday, he often returned to his favorite words, lexical touchstones that he looped back to again and again, providing a patina of coherence and structure to his stubbornly unstructured discourse.

Twenty-two times he said believe, though frequently to state disbelief. (“Nobody in this room believes it.” “Honestly, nobody knows who to believe.”) Love came up 13 times, as he managed to profess his affection for Canada, China, farmers, and even The New York Times. He relied on his usual fleet of positive and negative adjectives, with everything arrayed in a Manichaean dichotomy: on one side, incredible, tremendous, and beautiful; and on the other, horrible, bad, and (for news, of course) fake. Tellingly, he said his own name 15 times, whether it was to quote an unnamed expert who said that “China has total respect for Donald Trump and for Donald Trump’s very, very large brain,” or to implore a Times reporter to say “Thank you, Mr. Trump.”

But perhaps the most significant word of all for Trump was a three-letter one: con. More than a dozen times he used it in the phrases con artist, con job, or con game. First, he called out Democrats as “con artists” for destroying the reputation of his Supreme Court pick, Brett Kavanaugh, characterizing the mounting accusations of sexual misconduct as “a big fat con job.” The lawyer Michael Avenatti, representing one of the accusers, got singled out as a “con artist,” and he insisted that even “George Washington would be voted against 100 percent by [Senator Chuck] Schumer and the con artists.”

Amidst all of this “con” talk, Hannah Thomas-Peter from Sky News asked Trump, “Are you at all concerned at the message that is being sent to the women who are watching this when you use language like con job?” Trump interrupted her, saying, “I’ve used much worse language in my life than con job. That’s, like, probably the nicest phrase I’ve ever used.” He then offered an etymological lesson: “It’s a con job. You know, confidence. It’s a confidence job.” He proceeded into a discussion of the Russia investigation, which—you guessed it—is nothing but a “con job.” After all of that, he had the chutzpah to add, “And it’s not a bad term. It’s not a bad term at all.”

Let’s take a step back to look at this key element of Trump’s vocabulary. As he rightly stated, con is short for “confidence,” since it derives from the professional method of swindling victims by winning over their confidence and persuading them to part with their valuables. American newspapers of the mid-19th century were full of stories about “confidence men” running “confidence games” or “confidence tricks.”

The expression may have first cropped up in the pages of The New York Herald, which reported on May 30, 1847, that there was “an accomplished swindler” in the city and that “our sharpest business men have placed ‘confidence’ in him.” The next week, the Herald reported on the arrest of “a notorious thief”: “In all probability this is the man, from the description, who has ‘done’ the knowing ones around the city, commonly called the ‘confidence’ man.” When the Herald told of the arrest of another “confidence man” two years later, it garnered national attention, fixing the expression in the American lexicon. By the time Herman Melville published The Confidence-Man, in 1857, he could safely assume that the general public would understand the term.

By 1878, the swindling sense of “confidence” was so well known that it could be shortened to con, with the Chicago Tribune that year reporting on cases involving local criminals “playing the ‘con.’ game” and pulling “‘con.’ tricks.” The humorist George Ade, who helped popularize such slang expressions as okay and guys, also took con mainstream. His 1896 novel, Artie, has characters exulting in “large, juicy con talk,” and it also showcased the word’s use as a verb meaning “to deceive”: “Drop it! Don’t try to con me with no such talk.”

Twentieth-century fraudsters developed a whole taxonomy of “cons,” from “short cons” to “long cons.” The elaborate “long con” was also known as “the big con”—used as the title of a 1940 book by the linguist David Maurer, who studied con men and their slang. (One con described in the book would become the basis for the movie The Sting.)

By the time young Donald Trump was growing up in mid-20th-century Queens, “con jobs” and “con artists” were part of the urban scenery. Not surprisingly, the word shows up several times in the book he cowrote in 1987 with Tony Schwartz, The Art of the Deal. “I’ve always felt that a lot of modern art is a con,” he opines. A less-than-trustworthy project manager named Irving is described as “a con man” who “had done all sorts of con jobs and swindles.” And one of his major precepts in the chapter on “The Elements of the Deal” states, “You can’t con people, at least not for long … If you don’t deliver the goods, people will eventually catch on.” (Trump would quote this line in a 2011 tweet, directed at House Speaker John Boehner and Majority Leader Eric Cantor when they were pushing through their plan to resolve the debt-ceiling crisis.)

Trump likes to portray himself as a man who knows all the cons and can’t be conned himself. You could say that it takes one to know one. In the 2016 Republican primaries, Senator Marco Rubio referred to Trump on several occasions as a “con man” or “con artist,” a characterization he stood by even after dropping out of the race and supporting Trump as the nominee. And Schwartz, his Art of the Deal co-author, said on MSNBC last year that when Trump talks about con artists, it’s “classic projection”: “That notion that he’s a con man, believe me, that is deep inside what he knows himself to be.” No wonder he keeps inveighing against all the con jobs he imagines surrounding him, all the better to deflect attention from his presidential confidence trick.

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