Robert Gates was back in Washington this evening with a display of the understated candor that was a trademark during his five years as secretary of defense. It was Gates, after all, who last year described members of Congress as a group “with oversized egos and undersized backbones”—a line he cheerfully repeated during tonight’s award ceremony hosted by the National Academy of Public Administration. Gates, on hand to receive the academy’s Elliot L. Richardson Prize for excellence in public service, spoke during a wide-ranging question-and-answer session with James Kitfield, senior correspondent at National Journal. Here are a few other excerpts: *…