WHAT DO New York Times columnist Nicholas D. Kristof and tabloid biographer Kitty Kelley have in common? They share a source. Not that Kristof admits it, of course. In his September 15 column, the Pulitzer Prize winner tells the dramatic story of Yoshi Tsurumi, who taught President Bush at Harvard Business school. What you won't find in the column is any mention of the fact that Kitty Kelley broke the Tsurumi story in her new book, The Family. Here is Kristof: One fall day in 1973, when Mr. Bush was a new student at Harvard Business School, he was wearing...