The other day, I responded to David Frum's assertion that acceptance of same-sex marriage was making the traditional gender-specific roles within a marriage "unthinkable", pointing out that gender roles within heterosexual marriage had already evolved to a more egalitarian bargain on their own, independently of same-sex marriage. Frum, in fact, has it backwards. The traditional husband-master / wife-chattel model of marriage has been transformed into a more modern notion of a partnership of two equals, driven by an evolved understanding of gender equality more resonant with our instincts for liberty and justice. The concept of same-sex marriage has not been any kind of driver in this process, but rather has been a beneficiary. From a traditional understanding of marriage, with gender-specific roles, the concept of same-sex marriage is indeed a conundrum, raising the question of two same-sex partners: which one is the "husband" and which the "wife"? With an evolved understanding of marriage as a partnership of two equals, same-sex marriage becomes readily comprehensible. A modern husband and wife reach their own personal decisions about who plays what roles in earning of income, maintaining the home, and raising the children. It is no different for two husbands or two wives.
Ironically, just as gender equality makes same-sex marriage more comprehensible, it makes polygamy less so. Polygamy, as it is traditionally practiced, consists of a patriarch and his dependent wives. The roles are very gender-specific: the husband rules the wives, each wife depends on the husband, and the relationship among the wives is that of a "sister-wife" (a side-effect of their parallel primary relationships with the patriarch). Examples of this persist today in specific religious communities, such as fundamentalist Mormon offshoots in Utah, Arizona, and British Columbia, as well as some orthodox Islamic communities. The system requires subjugation of the women, with marriages often arranged while the women are still girls. In contexts such as these, sentiments like those expressed by David Frum for gender-role-dependent "special duties" between husbands and wives are more comprehensible. From a modern viewpoint, the subjugatory relationships inherent in traditional polygamy are harshly dissonant with our sensibility of individual liberty and equality. The instincts for justice and equality that have lead our society to gender equality, and which are leading our society to acceptance of same-sex marriage, are the same instincts for justice and equality that make traditional polygamy especially repugnant. On the other hand, those who cling to traditional gender roles, refusing to accept gender equality, lend unwitting support to the polygamists by defending the very traditions that make polygamy coherent. The modern cultural momentum toward spousal equality points in the direction of same-sex marriage, and away from polygamy. They are in opposite directions. Those who wish to reverse this momentum, moving our society back toward "traditional" (master/chattel) marriage, also would move us toward polygamy. Contrary to "conventional wisdom", it seems the traditionalists, such as David Frum and Maggie Gallagher, are the ones falling down the slippery slope just a step away from polygamy.