Elon Musk is tweeting up a storm, and he’s loving every minute of it. With 21 million followers, Musk has emerged as one of the defining Twitter voices of 2018, someone who will happily and democratically engage with anybody who @s him. Like other gazillionaires before him—Rupert Murdoch, Marc Andreessen—he’s found in Twitter a fun and unfiltered platform for self-expression. Unlike Murdoch and Andreessen, however, he’s still at it. And he needs to be stopped.