If you read Twitter recently, you'll have noted that a wide range of figures have changed their Twitter names to incorporate a series of parenthesis. The Atlantic's Jeffrey Goldberg, for example, is now (((goldberg))), and we've also got Center for American Progress president (((Neera Tanden))) and Politico finance writer (((Ben White))).

Even the internet satire account formerly known as Fake Jeff Jarvis has gotten in on the game, referring to itself as Prof. (((tronc))), combining the parenthesis fad with a joke about the publisher of the Chicago Tribune and the LA Times renaming itself tronc.

These renamings are themselves a response to an exciting new trend on the alt-right, a mostly online movement of mostly white nationalists who've gained new prominence largely thanks to Donald Trump's campaign. They've taken to identifying Jewish individuals and what they see as Jewish-controlled institutions by surrounding their names with parentheses — a typographical convention known as an echo.

An alt-right article or tweet, for example, might refer to this as a (((Vox))) explainer written by Matt (((Yglesias))) to signify that its author is Jewish despite a not-very-Jewish name and that Vox, like many American media establishments, features a number of Jewish writers and editors that is disproportionately high relative to Jews' presence in the overall American population.

The echo's popularity online signifies both the alarming increase in vocal and visible anti-Semitism associated with the Trump campaign and, in a practical sense, its limits. The echo is spreading so widely as a self-ascription because Jews themselves are adopting it as a gesture of defiance and reappropriation, and because non-Jews are adopting it as a gesture of solidarity designed to undermine the implicit threat.

The echo originates with The Daily Shoah podcast

As Cooper Fleishman and Anthony Smith detail for Mic, the origins of the echo date all the way back to 2014 episodes of a podcast called The Daily Shoah (Shoah is the Hebrew word for the Holocaust), which is affiliated with the leading alt-right site the Right Stuff.

The podcast, Fleishman and Smith write, "featured a segment called 'Merchant Minute' that gave Jewish names a cartoonish 'echo' sound effect when uttered."

As the official Right Stuff lexicon explains, this is because "all Jewish surnames echo throughout history. The echoes repeat the sad tale as they communicate the emotional lessons of our great white sins, imploring us to Never Forget the 6 GoRillion."

The parentheses are a visual pun on that idea of the echo.

Awareness of the echo spread thanks to a "coincidence detector" plug-in

People outside the alt-right began to learn about the echo when the New York Times's deputy Washington editor wrote a column about his experience with anti-Semitic online harassment from Donald Trump fans. It began with an encounter with the enigmatic echo:

THE first tweet arrived as cryptic code, a signal to the army of the "alt-right" that I barely knew existed: "Hello ((Weisman))." @CyberTrump was responding to my recent tweet of an essay by Robert Kagan on the emergence of fascism in the United States. "Care to explain?" I answered, intuiting that my last name in brackets denoted my Jewish faith. "What, ho, the vaunted Ashkenazi intelligence, hahaha!" CyberTrump came back. "It’s a dog whistle, fool. Belling the cat for my fellow goyim." With the cat belled, the horde was unleashed.

But what really brought the echo to mainstream attention was the brief history of the Coincidence Detector Google Chrome plug-in. This was a browser plug-in that linked to a database of Jewish individuals that, if installed, would automatically render all the names on the list with the echo. That was a quick and convenient way for online anti-Semites to stay up to speed on who is and isn't Jewish. When mainstream media coverage brought wide attention to the plug-in, Google killed it.

Now others are using solidarity parenthesis

Some of the people who've changed their Twitter names to incorporate the echo are Jewish, making a gesture of pride and reclamation. Others, however, are not Jewish but are simply doing it as a gesture of solidarity. The idea is that the act of singling out Jews for discrimination with a particular marker is thwarted if non-Jews choose to wear it voluntarily.

One particularly resonant cultural trope this reflects is the solidarity expressed by the government and people of Denmark with their country's Jewish population during its occupation by Nazi Germany. As Leon Uris recounts in his influential and widely read 1958 book Exodus:

From the German occupation headquarters at the Hotel D'Angleterre came the decree: ALL JEWS MUST WEAR A YELLOW ARMBAND WITH A STAR OF DAVID. That night the underground transmitted a message to all Danes. 'From Amalienborg Palace, King Christian has given the following answer to the German command that Jews must wear a Star of David. The King has said that one Dane is exactly the same as the next Dane. He himself will wear the first Star of David and he expects that every loyal Dane will do the same.' The next day in Copenhagen, almost the entire population wore armbands showing a Star of David. The following day the Germans rescinded the order.

As it happens, this story isn't true. Denmark really did feature a unique nationwide mobilization to rescue its Jewish citizens, but the yellow armband order was never given, so there was no need to take countermeasures.

The idea, however, is a powerful one, and it's helped inspire imitators even though the original isn't strictly real.

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