Peter Sprigg begins his new book on same-sex marriage, Outrage, with a paradox: Most Americans oppose it, "yet in terms of political action, the pro-family, pro-marriage majority has been strangely muted." Sprigg attributes this to a lack of intellectual ammunition and aims to remedy that deficiency with this book. He is certainly qualified to do so. Director of the Center for Marriage and Family Studies at the Family Research Council (FRC), Sprigg has also co-authored a more scholarly book published by FRC that assembles the scientific research on homosexuality. Some highlights of that research provide the factual foundation for...