I Studied Trump’s Twitter Use for Six Years. Prepare for the Worst.

The situation at Twitter has been chaotic. Over the past few weeks, new owner Elon Musk introduced a major product — and then paused it. He’s dismissed hundreds of employees — and then asked some of them to return.

But nothing Musk has done and undone is nearly as concerning as his decision to suddenly reinstate former President Donald Trump’s account. Like many of Musk’s decisions as the company’s “chief twit,” this one is hard to understand. Mr. Musk had previously said he wouldn’t reinstate any accounts until a content moderation council with “wildly diverse viewpoints” convenes. It’s unclear if a council was ever convened; Mr. Trump’s account was reinstated after Mr. Musk conducted an online poll, something he’s historically done to get buy-in for something he’s already decided to do.

While Mr. Trump has recently said he has no plans to return to Twitter, that position seems unlikely to stick given his need for attention, the challenges facing his social-media venture Truth Social and his recent announcement to run for president.

As someone who has been studying Mr. Trump’s Twitter use since before he was elected president, I believe that his return would mean the heightened spread of both misinformation and disinformation, the proliferation of degrading and dehumanizing discourse, the further mainstreaming of hate speech and the erosion of democratic norms and institutions. But there is something else: Mr. Trump’s return to Twitter could escalate the likelihood of political violence.

Simply put, if you are surrounded by dry kindling, add an accelerant and light a match, conflagration is the predictable outcome.

The most important factor in understanding why Mr. Trump’s possible return to Twitter is so dangerous concerns the structural similarity between the Twitter platform and the content of Mr. Trump’s rhetoric. Twitter’s strict 280-character limitation, its hyper-focus on what’s happening at any given moment and its ease of use distinguish it from other social media platforms that allow users to publicly share their ideas and opinions.

Like all forms of communication, the defining features of Twitter create inherent structural biases. The platform is well suited for communicating simple messages widely and quickly. But Twitter’s three primary structural biases — simplicity, incivility and impulsivity — make it a lousy platform for engaging in thoughtful, sustained discussion of serious matters related to the public interest.

Twitter also participates in and contributes to the broader communication ecosystem of social media. Social-media platforms are biased in the direction of divisiveness and dogmatism. The underlying structure of these platforms generally invites and encourages users to seek out like-minded people who, in turn, become even more convinced of the “correctness” of their views. Given that so much of our news and information is filtered through social media, much of what we are exposed to simply confirms what we already think.

But it’s not just about what we think; it’s also about how we feel. Social media platforms are uniquely adept at mobilizing emotion, especially negative emotion. When was the last time you encountered an angry, inflexible centrist who aggressively demanded that you see things from several points of view? Never. Basically, social media radicalizes us and primes us to be intolerant of others whose attitudes, opinions and views differ from our own.

So much for the kindling.

Given that our communication environment is structurally predisposed to heighten and cement our ever-growing political divide by telling us how right and righteous we are, one may reasonably wonder why I am concerned about one user in particular. First, a large number of people not only listen to Mr. Trump but also are inclined to take direction from him. Second, Mr. Trump combines divisiveness and dogmatism with hatred and angry rhetoric that risks inciting violence. For reasons better left to psychologists, Donald Trump is not content to forget or forgive people he perceives have wronged him. He wants to destroy them. So, he calls them out, often on social media, and then he goads his followers into doing something about it.

One of the fundamental premises of those who study rhetoric is that discourse always reveals motives. Mr. Trump’s discourse since losing the presidency in 2020 consistently suggests that he is motivated by one thing only: a desire for revenge. He wants to punish everyone who he perceives has wronged him, including anyone who has not shown unfettered fealty. For Mr. Trump, the desire for revenge has long involved symbolic violence in the form of speech that aggressively demeans and dehumanizes others. Such speech risks sparking material violence.

Mr. Trump’s willingness to share a conspiracy theory around the violence visited upon Paul Pelosi is a case in point, especially given that it appears Mr. Pelosi’s attacker was radicalized online. This sort of callousness and indifference is not new. Mr. Trump has long trafficked in violent and degrading imagery, and ever since losing the 2020 election, he has been mobilizing his army to act on it.

Since leaving office, he has amplified QAnon conspiracy theories, extremism and far-right ideas on Truth Social. A short time later, Mr. Trump told his followers that Senate minority leader Mitch McConnell had a “death wish” for approving a deal to fund the government through December. To ramp up emotions even further, Mr. Trump threw in a racist jab about Mr. McConnell’s wife. Fortunately, no harm came to Senator McConnell or his wife. But Mr. Trump has demonstrated a consistent willingness to invoke racially and sexually charged rhetoric that contains an implicit call to violence.

Trump is an accelerant; his message is a match.

Twitter and Mr. Trump represent a dangerous fusion of form and content. Social media generally and Twitter specifically lend themselves to simple, urgent, unreflective and emotionally charged communication. When the message is one of intolerance and violence, the result is all but certain.

Brian L. Ott, professor of communication at Missouri State University, is a co-author of “The Twitter Presidency: Donald J. Trump and the Politics of White Rage.”

The Times is committed to publishing a diversity of letters to the editor. We’d like to hear what you think about this or any of our articles. Here are some tips. And here’s our email: [email protected].

Follow The New York Times Opinion section on Facebook, Twitter (@NYTopinion) and Instagram.