For men of a certain age, learning to tie a tie was a rite of passage. The necktie is a sign of maturity, self-discipline and respect for tradition. The knot in one’s necktie is a biography in silk, communicating details of temperament, character and upbringing. Bulky Double Windsors are brash and extroverted. Perfectly symmetrical knots with centered dimples betray an obsessive-compulsive personality. The Italians have mastered the insouciance of the slightly off-center knot — some even leave the narrower end a bit longer, letting it peek out from behind the thicker one in front, as if to say, I really couldn’t be bothered to redo it.

Trump partisans may well complain: Why is the Italian imperfect tie-knot considered chic and the presidential idiosyncrasy déclassé? Isn’t this a double standard set up by liberal elitists?

As with most sartorial conventions, there is an underlying logic. The long, fat end of Mr. Trump’s tie, flapping in the breeze like an advertising banner or swinging far beneath his belt, is both overly contrived and disproportionate. By contrast, the Italian’s slightly askew tie is visually balanced and charmingly unselfconscious. If the Italian’s tie shows an aristocratic disdain for the trappings of masculine potency, Mr. Trump’s symmetrical but overlong tie stands out like a rehearsed macho boast, crass and overcompensating. In past eras such posturing could be unlawful: The overstuffing of one’s codpiece, for instance, was considered such an affront to public order in Renaissance England that offenders were forced to march through the streets with their stuffing pulled out — their deception exposed for all to see.

And then there is the matter of the tape. This is the opposite of the Italian’s devil-may-care. It betrays a devil who cares too much — and about the wrong things. Whereas the slightly imperfect tie knot demonstrates nonchalance, the badly tied and taped tie suggests a desperate but failed bid to look “correct.” It’s not only a failure, but also a fraud, a paper moon artlessly stuck over a cardboard sea.

Mr. Trump’s neckties tell us something about his social and political ties. He has made the persona of the loud, tacky mogul a sort of trademark. Many of his supporters cheer him on because of his lack of refinement — they consider him a refreshing change from patrician politicians born with a silver tie bar clutched in their long elegant fingers. Mr. Trump comes off as a plebeian hero in spite of his inherited wealth because he did not inherit the sensibilities of the elite. He may have grown up in a plutocrat’s manor, but he was not to the manner born.