In a single fleeting moment Tuesday night during President Trump’s State of the Union address, shown for only seconds on live broadcasts but immortalized in photos and GIFs, House Speaker Nancy Pelosi (D-Calif.) became the Internet’s newest obsession — for clapping.

Despite being engaged in a tense standoff with Trump over funding for his border wall, for most of the evening, Pelosi managed to limit her reactions to subtle head-shaking, pursed lips and eye rolls during the speech. She and Vice President Pence sat behind the president, who took his place at the front of the House chamber. But when Trump, who has been accused of exacerbating deep divisions, declared, “We must reject the politics of revenge, resistance and retribution and embrace the boundless potential of cooperation, compromise and the common good,” she appeared to be unable to hold back.

Rising from her seat along with others in attendance, Pelosi began applauding with her arms oddly extended out toward the president. When Trump turned toward her and the pair locked eyes, Pelosi, still clapping, appeared to smirk.

Trump was supposed to be the center of attention during the address, which, at 1 hour 22 minutes, was the third-longest State of the Union speech in modern history. But as late-night host Seth Meyers reminded his audience during Tuesday’s special live show covering the speech, “There’s a long history of the people sitting behind the president getting as much attention as the president himself.”

Beyond the clapping, Pelosi’s overall mood during the address also did not go unnoticed. Described by The Washington Post’s Mike DeBonis as “the face of Democratic exasperation,” Pelosi seemed rather uninterested by Trump’s lengthy speech, many pointed out, unlike her neighbor, a moderately animated Pence. In some instances, she chose to stare at a sheaf of papers in front of her instead of at the president.

“She looks like a babysitter reading the rules of a board game while the kids are just chucking game pieces at each other,” Meyers quipped.

Twitter goes wild

Social media users proceeded to lose their collective minds when Pelosi clapped. As many put it, Pelosi had just effectively issued a “literal clap back” to the president on national television and in front of a room full of the country’s most powerful people. By early Wednesday morning, Pelosi’s clap was a trending moment on Twitter, and she had been mentioned in more than 222,000 tweets.

“Respect to Pelosi,” one Twitter user wrote. “Circumstance demanded she clap, so she invented this weird walrus clap that was mocking, aggressive, and delightfully surreal all at the same time.”

“Nobody has ever has clapped like this.”

Pelosi was crowned the “Queen of Condescending Applause,” and the picture of her clapping was celebrated as the “photo of the century.”

Others, such as actor and comedian Patton Oswalt, credited Pelosi with creating a new type of clap — named after an explicit two-word exclamation commonly used to convey anger or contempt.

It didn’t take long for Pelosi to once again inspire viral memes (remember disappointed parents and the red coat?), including, but certainly not limited to, this thread:

Some likened Pelosi to equally snarky fictional characters, such as Hermione Granger from the “Harry Potter” series and Lucille Bluth of “Arrested Development.”

The clap, however, was not appreciated by everyone.

“That just seems immensely petty and childish,” one person tweeted.

Another person commented, “Huge disrespect shown by a ridiculous woman that is chewing on something and looking at her art papers/menus/notes on when to sit down, through the entire evening.”

Late-night hosts weigh in

Appearing on “The Late Show With Stephen Colbert,” which also went live Tuesday night, “CBS This Morning” co-host John Dickerson joked that it “didn’t look like Trump sparked joy” for Pelosi, using a phrase popularized by Marie Kondo, a Japanese professional organizer who advises people to purge their homes of items that no longer “spark joy” for them.

“She’d like to Marie Kondo him out of the House,” Colbert replied.

Theories abounded about what Pelosi could have been reading that was more riveting than Trump.

On his live edition of “The Daily Show,” Trevor Noah suggested she was perusing a menu, adding, “I kept expecting a waiter to come over with an order of Buffalo wings.”

The official Twitter account of “Full Frontal With Samantha Bee” was convinced that Pelosi was absorbed in “a Jodi Picoult novel.”

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