Sarah Posner: Two weeks ago, I wondered whether, based on a WorldNetDaily smear job linking her to communists and other nefarious people, White House adviser Valerie Jarrett would be Glenn Beck's next target. Today, referring to Yosi Sargent's resignation from the National Endowment for the Arts, Beck is saying on his radio program that Sargent is small fry. "The one you need to start asking questions on is Valerie Jarrett. . . . it's the ones at the top of the ladder that you have to pay attention to."