It’s a gesture familiar to anyone who’s ever been warned, cautioned, scolded, told they are not very nice or otherwise belittled. A hand, often the dominant one, is raised. An index finger is extended skyward. The finger moves from left to right in a workmanlike arc or, for those with more rococo tastes, a flamboyant circle. Sometimes, a pen adds gravitas to the motion. Though the tempo and exact meaning may vary, the message is always similar, and always at least a little bit threatening. I know better than you. You are making a huge mistake. Back off.  

No politician in modern memory seems to favor the finger wag as much as Democratic presidential contender Sen. Bernie Sanders (I-Vt.). And people are starting to talk about it.

“Sanders … likes to wave his index finger in the air like he just don’t care … although it’s clear when he does it that he actually does care very, very much,” Alex Gladu wrote at Bustle. “The gesture is sort of a mix between scolding his opponent — typically Clinton — and screaming for attention.”

Though no official count was available, Sanders wagged his finger, at minimum, 13 times during Thursday night’s debate with Hillary Clinton in Milwaukee. He wagged when discussing the costs of his health-care plan. He wagged during a heated foreign policy discussion with his rival. He wagged when she cited his past criticisms of President Obama.

“Do senators have the right to disagree with the president? Have you ever disagreed with a president? I suspect you may have,” he shot back, finger in full force.

Of course, Sanders is not the only politician in history to have a signature gesture. Indeed, legacies are often made or broken by body language. Consider: Theodore Roosevelt’s chiseled smile. Franklin Delano Roosevelt’s grimace, usually wrapped around a cigarette holder. Richard Nixon’s scowl — and the scowl that cost George W. Bush a debate against John Kerry in 2004. Bill Clinton’s thumb-pointing. And Donald Trump’s contemptuous shrug.

But in the hard-fought winter of an election year, gestures mean a lot. And Sanders caught some flak for a move some thought condescending.

“I think wagging a finger has an implications [sic] of shaming or pretend authority while waving arms is more expressive,” one commenter on a Mother Jones piece from last month wrote. “I wish he’d do it less, it makes me think of Nixon.”

Worse: In a debate against Clinton, who’s trying to become the first woman president, a little bit of wagging can be perceived as sexist.

“Sanders showed his disdain for a powerful intelligent and assertive woman with that damn finger wagging,” one Clinton supporter wrote on Twitter.

Some Clinton critics complain about her tone, saying she comes off as nagging or shrill. (Recently from the Huffington Post: “People Won’t Stop Criticizing Hillary Clinton For Raising Her Voice” and from the New York Times: “Hillary Clinton Raises Her Voice, A Debate Over Speech and Sexism Rages.”

Isn’t Sanders guilty of the same thing — and getting a pass because he’s a man? As another Twitter user boldly put it: “IF YOU [Expletive deleted] WAVE YOUR FINGER ONE MORE TIME WHILE SHE IS SPEAKING I WILL PERSONALLY BOYCOTT THE STATE OF VERMONT FOREVER.”

Others, however, thought Sanders should wag with pride. Perhaps he just can’t help it being from Brooklyn, one comment on Twitter suggested. “They talk with their hands!”

On a less serious note, some noted the wag’s similarity to that of former NBA basketball player Dikembe Mutombo.

Whatever the implications of the Vermont senator’s go-to maneuever, it’s clear that his supporters will follow wherever his finger leads them. As one Sanders enthusiast put it Thursday night: “If I could get a Bernie Sanders “Finger Wag” GIF tattoo; I’d freaking get that thing TOMORROW!”