On today's show: A Vanity Fair reporter exposes two C.I.A. psychologists who used their military training to create the torture tactics used at Guantánamo Bay. Also, a new documentary traces bad policy decisions in Washington to their disastrous effects on the ground in Iraq. Then, an Iraqi writer discusses his debut novel about life under Saddam Hussein. And on this week's Please Explain, we put aside Harry Potter to learn the truth about magic, witchcraft, and wizardry.