Donald Trump is big on Twitter. Just as F.D.R. spoke directly to the American people through his “fireside chats,” so too does Trump pontificate on the pressing issues of the day, such as the merits of certain Broadway musical or whatever’s on cable news at the time, through his Android phone. As is his wont, this week the president-elect took to Twitter to focus his attention on Chuck Jones, the head of the local steelworkers union in Indianapolis. Jones had criticized Trump for allegedly misleading the public about the deal he had struck with Carrier to prevent hundreds of jobs at two Indiana factories from moving to Mexico. Trump boasted that the agreement—which involved giving the company a $7 million tax break—would save 1,100. Jones pointed out that the real number was far less.

“He got up there and for whatever reason, lied his ass off,” Jones told The Washington Post. Later, he continued to chide the president-elect in a follow-up interview on CNN. “What nobody is mentioning is that 550 people are losing their jobs.”

Trump immediately took to Twitter to vent to his more than 17 million followers. “Chuck Jones, who is President of United Steelworkers 1999, has done a terrible job representing workers. No wonder companies flee country!” he wrote. In a second message, he added: “If United Steelworkers 1999 was any good, they would have kept those jobs in Indiana. Spend more time working-less time talking. Reduce dues.”

Jones says he has since received threats from Trump’s supporters. “I’m getting them all day long—now they’re kicked up a notch,” the union leader said Wednesday. Nor is Jones the only Trump critic to be targeted. Lauren Batchelder, who was 18 years old when she questioned Trump’s treatment of women and his stance on abortion, received death and rape threats after Trump singled her out on Twitter. In total, Trump has insulted at least 300 people, places, and things since the start of his campaign, at least by The New York Times’s tally.

If he were anyone else, Trump may already have been reported to Twitter for abusing its terms of use. But banning the soon-to-be-president from his medium of choice appears unlikely. While the problem of online harassment has hamstrung Twitter’s efforts to sell itself—Salesforce is said to have walked away from a potential bid because of all the negative publicity surrounding the issue—eliminating its most prolific troll would likely backfire. Suspending Trump would certainly send a message that Twitter C.E.O. Jack Dorsey takes harassment seriously, but it would also politicize the company at a time when most of corporate America—including Twitter’s potential suitors—are hoping to make nice with the incoming administration. For many publicly-traded companies, appeasing the president is now part of their fiduciary duty.

In any event, Twitter is not going to remove Trump from its platform unless he unambiguously violates its guidelines, and he hasn’t quite done that yet. While he frequently attacks private citizens on the service, Trump has never explicitly called for violence. And despite its new policy of more aggressively targeting abuse, the social-media giant remains highly sensitive to accusations of censorship. “We believe in freedom of expression and in speaking truth to power, but that means little as an underlying philosophy if voices are silenced because people are afraid to speak up,” Twitter’s rules state. That carefully constructed language seems designed to leave Twitter plenty of room to maneuver. More important, what would Twitter be without Trump? The president-elect routinely drives an entire news cycles with his tweets—last week, he declared the diplomatic equivalent of war on China—making Twitter both essential reading and a critical fixture of the media ecosystem. Trump may be Twitter’s biggest troll, but his presidency is also the clearest confirmation of its power.