The novel that launched the Beats, the hippies and designer jeans turns 50. But this legendary 'joyride' is actually the saddest book you'll ever read—even with God on every page. Jack Kerouac's "On The Road" gets the full 50th anniversary treatment next month, and both cheerleaders and hand-wringers acknowledge that it radically changed American culture—somehow or other. True, the National Quiet Desperation Index has only risen since 1957, and if the book's exaltation of junker cars and diner food had really taken hold, we'd have fewer SUVs and fast-food franchises. But "On the Road" showed, and continues to show, generations...