There are nine announced contenders for the Democratic nomination for president, and as of this week, all nine have either written a book or had one written about them. “Some are good, some are bad. Some are thick, some are thin. Some are short, some are shorter. Some are direct, some are long-winded. And that goes for their books, too.” But seriously, when exactly did published authorship become a necessity of a serious presidential campaign? And what makes them think that we’re interested in reading their largely predictable tomes?