Both Ken and Jon throw around this phrase, traditional marriage, as though marriage hasn't changed drastically in the last century and a half or so - and as though "the family" that Jon is so worried about protecting - a nuclear family consisting of one husband, one wife, and their immediate offspring - isn't a product of the 1950s…
I have major issues with the institution of marriage, as it is now and as it has been used in the past - but I'd be wary of throwing around "traditional marriage" and the "traditional family" too often in your arguments for and against gay marriage in the future. Traditionally, marriage has transferred ownership of a woman from her father to her husband. Anything beyond that is a relatively new development. Traditionally, family has been much different than a husband, a wife, and their children.
To the contrary, Anna, marriage has not changed dramatically in recent times. Marriage is an ancient and ubiquitous institution (like prostitution and the priesthood). In almost all cultures, it is celebrated by very old symbols; for that reason, traditional has a pretty clear meaning.
Anna's statement that the "nuclear family… is a product of the 1950's", and that "traditionally, family has been much different than a husband, a wife, and their children," are certainly part of the conventional wisdom about marriage. Like much CW, they are obviously wrong.
Across history and cultures, marriage has always been about a man, a wife, and their children. The fact that some marriages are childless is irrelevant to the institution's basic function. Marriage has three basic forms: monogamous, polygynous, and polyandrous. Until recently, most human societies practiced some form of polygyny, but that was a privilege of men who could support more than one wife. Most families in such societies were monogamous out of necessity. Polyandry is extremely rare (only two cultures are well known), owing to the fact that women can have only so many children in a given span of time. To the degree that two or more men confine themselves to one woman, the population growth of that society will be limited.
To be sure, the "nuclear family" is not so common; in most societies, extended families and clans were much more important than they are in modern societies. But these larger families weren't "marriages", they were networks of marriages. Marriages were, until recently, always about a man, his wife or wives, and their children.
As for the feminist party line statement—"traditionally, marriage has transferred ownership of a woman from her father to her husband"—here Anna is doing what she accuses us of doing: projecting modern notions (in this case, modern property rights) backwards into the past. In most cultures, marriage was more akin to naturalization than to a contract exchange. Human cultures have been mostly patrilinear; men stayed put while women were exchanged between clans, villages, etc. To be sure, such exchanges were greased with gifts (dowries), but that was true of a lot of social intercourse. And to be sure, fathers had a dominant position in the negotiations. But that is a result of the patriarchy that characterized almost all pre-modern societies.
Specifically modern notions of property rights (see John Locke) had the inevitable effect of raising the wife and daughter to equal status with the father and suitor. I think that's progress. So I wouldn't be so quick to condemn the concept of ownership in such things.
But the modern notion is not "a drastic break from tradition," as Anna would have it. It is, as much of modern life, a modification of the traditional. Gay marriage is an unprecedented extension of the ancient institution. I am in favor of it, but it is obviously valuable if and only if it extends the benefits of the tradition to a new class of couples. For that reason, I think our use of the term "traditional marriage" is entirely appropriate.
Ps. I have missed you, Anna. I hope things are going well for you.