The host of “WTF with Marc Maron” remembers when he first realized he had a future in broadcasting: high on coffee and M&M’s, he started ranting about feral cats on Air America, and it killed. More than six hundred episodes of his podcast later, he joins The New Yorker’s Kelefa Sanneh to talk about his famous heart-baring argument with Louis C.K., what he learned from Rush Limbaugh, and that time the President came to his garage for an interview.