WASHINGTON -- When Massachusetts' highest court asserted that same-sex marriage is a right protected by the state's constitution and entailed by recent U.S. Supreme Court reasoning about the U.S. Constitution, the president vowed to ``do what is legally necessary to defend the sanctity of marriage.'' His vow implied two empirical premises for which conclusive evidence is lacking.
One is that law can do what the culture -- immensely powerful and largely autonomous -- has undone. The other is that the social goods and individual virtues that marriage is supposed to buttress are best served by excluding same-sex couples from the culture of marriage, lest that culture be even more altered than it recently has been.
More than 40 percent of America's first marriages end in divorce. Cohabitation by unmarried heterosexual couples has risen rapidly from 523,000 in 1970 to 4.9 million today. Procreation outside of marriage, although the seedbed of millions of individual tragedies and myriad social pathologies, has lost much of its stigma now that 33 percent of births -- including about 60 percent of births to women younger than 25 -- occur to unmarried mothers.
So the ``sanctity'' of American marriage is problematic. The crucial question is: Because the public meaning of marriage -- the reason there are laws about it -- is procreation and childrearing, what would be the consequences of altering the public meaning of marriage by including same-sex unions?
The rapid decline of a foundational social institution, such as marriage in the last four decades, and the attendant rise of social disorder, usually correlates with some immense event, such as war. But the decline of marriage -- and the rise of what are no longer called illegitimate births -- has occurred during four decades of mostly peace and prosperity.
Some reasons for this are unclear, others seem impervious to legislative remedies. Therefore one cannot confidently assert the consequences of expanding, or pre-emptively restricting, the definition of marriage. But one near certainty is that establishing the right to same-sex marriage by judicial fiat rather than democratic persuasion will retard, and perhaps reverse, growing tolerance of homosexuality.