Melissa Joskow / Media Matters Jack Posobiec, a conspiracy theorist and consummate pro-Trump media figure who often boasts of his access to the White House and other MAGA celebrities, worked as recently as 2017 with white supremacists who advocate for violence. Posobiec has a long record of extremism and ratfucking: He was an outspoken advocate of the “alt-right,” published a book with the help of an “alt-right” figure, and pushed all kinds of smears and misinformation for political gain. Posobiec reportedly had links to Jeffrey and Edward Clark, two white supremacist brothers.