Thanks, Shari, to this link to a speech given by Lois McMaster Bujold. A tantalizing excerpt:

In fact, if romances are fantasies of love, and mysteries are fantasies of justice, I would now describe much SF as fantasies of political agency. All three genres also may embody themes of personal psychological empowerment, of course, though often very different in the details, as contrasted by the way the heroines “win” in romances, the way detectives “win” in mysteries, and the way, say, young male characters “win” in adventure tales. But now that I’ve noticed the politics in SF, they seem to be everywhere, like packs of little yapping dogs trying to savage your ankles. Not universally, thank heavens — there are wonderful lyrical books such as The Last Unicorn or other idiosyncratic tales that escape the trend. But certainly in the majority of books, to give the characters significance in the readers’ eyes means to give them political actions, with “military” read here as a sub-set of political.