To get a sense of why conspiracy theories centered on sex trafficking and pedophilia — and now the “Epstein list” — are so buzzy in MAGA circles, POLITICO Magazine called up Mike Rothschild, author of The Storm Is Upon Us: How QAnon Became a Movement, Cult, and Conspiracy Theory of Everything and Jewish Space Lasers: The Rothschilds and 200 Years of Conspiracy Theories. Rothschild pointed to a toxic stew of age-old antisemitism; the worst incentives of today’s social media; and the right’s unending obsession with Bill and Hillary Clinton. Donald Trump pops up in the documents, including some released on...