When terrorists struck Paris, they took aim at what binds us together as a society: our culture. And looking back at 15 years of terror, that’s nothing new. Near East scholar Bernard Haykel shows how ISIS uses poetry as propaganda. Pakistani-American columnist Rafia Zakaria calls the attacks an assault on fun — and explains why that’s much more serious than it sounds. Also, we hear how Sly and the Family Stone provided the soundtrack for freedom. And writer Gavin McCrea talks about his first novel, which imagines what it was like to love the co-author of “The Communist Manifesto.”