One sweltering DC evening many months ago, Ann Friedman, 29, then an editor for The American Prospect, sat with her friends Annie Lowrey, a reporter for Slate; Suzy Khimm and Kate Sheppard, reporters for Mother Jones; Marin Cogan, a reporter for Politico; Phoebe Connelly, a freelance writer and former web editor for The American Prospect; Britt Peterson, an editor at Foreign Policy; Dayo Olopade, a writer for The Daily Beast, Kay Steiger and Shani Hilton, editors at Campus Progress; Kat Aaron, a reporter for the Investigative Reporting Workshop; Monica Potts, a blogger for The American Prospect; Amanda Terkel, a reporter for The Huffington Post; and Laura McGann and Sara Libby, editors for Politico, at a bar on U Street. Ms. Friedman spoke about her younger — well, relatively younger — days in the city. “Everyone’s gotten a little bit older and a little more tired of being constantly rendered invisible,” Ms. Friedman said, speaking of a wave of Washington women journalists who have come of age together.