Sarah Palin called David Letterman "pathetic" after he joked about Alex Rodriguez getting her daughter pregnant and called Palin's appearance "slutty". From Worldmag:
In his Top Ten highlights of Sarah Palin’s visit to New York, Letterman referred to Palin’s wardrobe dramas, joking that she went to Bloomingdale’s to buy makeup to update her “slutty flight attendant look.” He also joked, referring to her visit to Yankee Stadium, that Alex Rodriguez got Palin’s daughter pregnant. While the joke obliquely refers to Bristol Palin, Jim Treacher said that the joke is especially offensive because Willow — Palin’s 14-year-old daughter — went to the game, not Bristol: “A national talk show host made a joke about the girl being sexually assaulted by one of the players.”
Palin responded on John Ziegler’s show by calling Letterman “pretty pathetic,” saying it was “very sad not to recognize, here again, truth and what this trip is all about. … Just doing some good things here for some good people in New York.”
Now, David Letterman has responded and, yes, his response is "pathetic". From EW.com:
“We were, as we often do, making jokes about people in the news and we made some jokes about Sarah Palin and her daughter [Bristol]... and now they’re upset with me…” Letterman says on tonight's show. "These are not jokes made about her 14-year-old daughter. I would never, never make jokes about raping or having sex of any description with a 14-year-old girl.... Am I guilty of poor taste? Yes. Did I suggest that it was okay for her 14-year-old daughter to be having promiscuous sex? No." Saying he hopes he's "cleared part of this up," Letterman extended an invitation to Palin to come on the show as a guest.