For intellectual heft, the capacity to spark debate and controversy, the number of young people inspired by her writing over the decades, the endurance of her ideas as the basis of a philosophical movement, the broad influence of those ideas -- and oh yes, for the number of books sold -- she was the most important American author of the post-World War II era. And on this, the week of the 50th anniversary of publication of her greatest work, "Atlas Shrugged," if you happen to disagree with that assertion, Ayn Rand would not be at all bashful in pointing out...