Al Gore and his wife Tipper, who once raged against provocative lyrics in popular music, have co-authored a book, Joined at the Heart: The Transformation of the American Family, that devalues traditional family life and promotes same-sex marriage. The volume—published with a companion photo album, The Spirit of Family—ranked a reassuring 4,041st in sales at Amazon.com on December 5. The Gores conclude that historian Tamara Hareven "summed it up eloquently when she told us, ‘The American family is not breaking down . . . it’s undergoing major changes, and pluralism has become a very important aspect of it." The Gores...