One reason why supporters of traditional marriage are losing elections is that they are losing the war for intellectual credibility. They are too often mired in facile arguments about “tradition”, Bible passages, and bleeding heart litanies about children. Supporters of gay marriage have succeeded in ridiculing these fumbling attempts at a rationale as ignorant and homophobic.
Indeed. You can't win by making the case against redefining marriage until you make a case for the current definition of marriage. Here is one attempt to address that.
In 2010 [Sherif Girgis is a Ph.D. student in philosophy at Princeton and a J.D. candidate at Yale Law School and Ryan T. Anderson, William E. Simon Fellow at the Heritage Foundation and editor of the Witherspoon Institute's journal Public Discourse, is a Phi Beta Kappa and magna cum laude graduate of Princeton University and a Ph.D. candidate in political philosophy at the University of Notre Dame] published a controversial article in the Harvard Journal of Law and Public Policy, putting forward a philosophical defence for the conjugal view of marriage. It gained many responses from all sides of the debate and has proved so successful that they have expanded it into a book to further flesh out their claims and answer their opponents.
The authors start by contrasting, with precision, the “conjugal” and the “revisionist” views of marriage. The conjugal view presupposes an exclusive union between a man and a woman that is bodily and mental and distinguishes itself by its comprehensiveness, while, revisionists claim that marriage is just two (no more, for the moment) people committing to romantically love and care for each other for as long as they see fit.
Marriage, as it has been understood for centuries, is a unique and comprehensive institution that joins mothers and fathers to their children and to each other. The authors show that it is a rationally defensible cornerstone of Western civilisation and a bedrock of societal stability. In confronting the challenge currently facing marriage in parliaments, courtrooms and schools around the world Girgis, Anderson and George put forth a clear and formidable case for one of our most sacred traditions.