© Evan Vucci—AP/Shutterstock President Donald Trump pumps his fist during a campaign rally at the Ford Center, in Evansville, Ind, August 30, 2018.

The opening shot of the war was fired on May 4, 2009. By all appearances, it had nothing to do with war.

“Be sure to tune in and watch Donald Trump on Late Night with David Letterman as he presents the Top Ten List tonight!”

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When @realDonaldTrump blasted his first bland tweet into the ether, there was little to distinguish the account from the horde of other brands, corporations, and celebrities who had also joined “social media.”

This constellation of emerging internet services, where users could create and share their own content across a network of self-selected contacts, was a place for lighthearted banter and personal connections, for oversharing and pontification, for humblebrags and advertising. That the inveterate salesman Donald John Trump would turn to it was not surprising.

Yet beneath the inanity, Twitter, Facebook, YouTube, and the like were hurtling toward a crossroads—one that would soon see them thrust into the center of civic life and global politics. Just a few years earlier, Twitter had begun as a way for groups of friends to share their “status” via text message updates. Now with 18 million users spread around the world, the startup was on the brink of a revolutionary success.

But it would be driven by a different celebrity. A few weeks after Trump’s first tweet, superstar entertainer Michael Jackson died. His passing convulsed the internet in grief. Pop music’s irreplaceable loss, however, proved Twitter’s gain. Millions of people turned to the social network to mourn, reflect, and speculate. The platform’s traffic surged to a record 100,000 tweets per hour before its servers crashed. People were using social media for something new, to experience the news together online.

© Catalyst Images Republican presidential candidate Donald Trump holds up a Donald Trump mask during a campaign speech, Monday, Nov. 7, 2016, in Sarasota, Fla. (AP Photo/Chris O'Meara)

Trump was also at a crossroads. The 63-year-old real estate magnate had just suffered his fourth bankruptcy when Trump Entertainment Resorts (the holding company for his casinos, hotels, and Trump Marina) collapsed under a $1.2 billion debt and banished him from the executive board. Although he had successfully rebranded himself as a reality-tele- vision host, that shine was starting to wear off.

While he would later talk about it as a top-rated show, The Apprentice had actually fallen from its early prime-time heights to the 75th most watched show, before being put on hiatus. The celebrity spin-off that Trump was promoting was still on the air, but its ratings were also plummeting. His appearance on Letterman was an attempt to stanch the bleeding. It wouldn’t work. In The Celebrity Apprentice’s season finale, just six days after Trump’s first tweet, more Americans would elect to watch Desperate Housewives and Cold Case.

But the transformation played out slowly, at least for the internet. Trump’s initial online messaging was sporadic, coming once every few days. In the first years of life, @realDonaldTrump was obviously penned by Trump’s staff, much of it written in the third person. The feed was mostly announcements of upcoming TV appearances, marketing pitches for Trump-branded products like vitamins and key chains, and uninspired inspiring quotes (“Don’t be afraid of being unique — it’s like being afraid of your best self ”).

© Catalyst Images President Donald Trump listens to a question while meeting the media in the lobby of Trump Tower in New York, Tuesday, Aug. 15, 2017. (AP Photo/Pablo Martinez Monsivais) But in 2011, something changed. The volume of Trump’s Twitter messages quintupled; the next year, it quintupled again. More were written in the first person, and, most important, their tone shifted. This @realDonaldTrump was real. The account was also real combative, picking online fights regularly — comedian Rosie O’Donnell was a favorite punching bag—and sharpening the language that would be- come Trump’s mainstay. His use of “Sad!,” “Loser!,” “Weak!,” and “Dumb!” soon reached into the hundreds of occurrences. Back then, it still seemed novel and a little unseemly for a prominent businessman to barrel into online feuds like an angst-ridden teenager. But Trump’s “flame wars” succeeded at what mattered most: drawing attention.

As the feed became more personal, it became more political. Trump issued screeds about trade, China, Iran, and even Kwanzaa. And he turned President Barack Obama, whom he’d praised as a “champion” just a few years earlier, into the most prominent of his celebrity targets, launching hundreds of bombastic attacks.

Soon the real estate developer turned playboy turned reality show entertainer transformed again, this time into a right-wing political power. Here was a voice with the audacity to say what needed to be said, all the better if it was “politically incorrect.” Not coincidentally, Trump began to use the feed to flirt with running for office, directing his Twitter followers to a new website (which had actually been created by his lawyer Michael Cohen). ShouldTrumpRun.com, it asked.

© Catalyst Images Republican presidential candidate Donald Trump speaks at a campaign rally in Akron, Ohio, Monday, Aug. 22, 2016. (AP Photo/Gerald Herbert)

The technology gave Trump immediate feedback, both validation that he was onto something and a kind of instant focus-testing that helped him hone and double down on any particularly resonant messages. Resurrecting an old internet conspiracy, Trump attacked not just Obama’s policies but his very eligibility to serve. (“Let’s take a closer look at that birth certificate.”) The online reaction spiked. Together, Trump and Twitter were steering politics into uncharted territory.

Through social media, Trump was both learning how the game was played online and creating new rules for politics beyond it. All those over-the-top tweets didn’t just win fans. They also stoked an endless cycle of attention and outrage that both kept Trump in the spotlight and literally made him crave more and more.

The engineers behind social media had specifically designed their platforms to be addictive. The brain fires off tiny bursts of dopamine as a user posts a message and it receives reactions from others, trapping the brain in a cycle of posts, “likes,” retweets, and “shares.” Like so many of us, Donald Trump became hooked on social media. In the three years that followed, he would personally author some 15,000 tweets, famously at all hours of the day and night.

Exactly 2,819 days after his first tweet, @realDonaldTrump would broadcast a vastly different announcement to an incomprehensibly different world. It was a world in which nine-tenths of Americans now had social media accounts and Twitter alone boasted 300 million active users. It was a world shaped by online virality and “alternative facts.”

And it was one in which the same account that had once informed hundreds of readers that “everybody is raving about Trump Home Mattress” now proclaimed to hundreds of millions, “I am honered to serve you, the great American people, as your 45th President of the United States!” That it had a typo showed the authenticity of @realdonaldtrump and what he would soon explain as “My use of social media is not Presidential – it’s MODERN DAY PRESIDENTIAL.”

© Catalyst Images Republican presidential candidate Donald Trump pumps his fist as he arrives to speak during a campaign rally, Monday, Nov. 7, 2016, in Manchester, N.H. From back left are Eric Trump, Vanessa Trump, Donald Trump Jr., Republican vice presidential candidate Gov. Mike Pence, R-Ind., Karen Pence, Ivanka Trump, Jared Kushner, and Tiffany Trump. (AP Photo/ Evan Vucci) The story of Trump’s first tweet though is not merely about the start of Trump presidency. Instead, it illustrates how a new kind of communications became a new kind of war. Trump’s quest to rebrand himself and then win the White House wasn’t just a marketing or political campaign; it was also a globe-spanning information conflict, fought by hundreds of millions of people across dozens of social media platforms, none of which had existed just a generation earlier. Not just the battlespace was novel, but the weapons and tactics were, too. When Trump leveled his first digital barbs at Rosie O’Donnell, he was pioneering the same tools of influence that he would use to win the presidency — and to reshape geopolitics soon thereafter.

© Catalyst Images Republican presidential candidate Donald Trump speaks at a campaign rally in Akron, Ohio, Monday, Aug. 22, 2016. (AP Photo/Gerald Herbert) Nor was Trump alone in this fight. As his battle for attention and then election was taking place, thousands of others were launching their own battles on social media. The participants ranged from fellow politicians and celebrities to soldiers, criminals, and terrorists. Organizations that ranged from ISIS to Russian information warriors to Chicago gangs all were at play in the same space, and often using the very same tactics, going after the very same targets. Conflicts of popularity and perception began to merge with conflicts of flesh and blood. As the stakes of these online struggles increased, they began to look and feel like war.

This essay is adapted with permission from LikeWar: The Weaponization of Social Media.