Why? It challenges gender roles. It decouples gender from biological sex, and women's sexuality from heterosexual procreation (a process started by The Pill). It challenges the patriarchy and its rigid adherence to biology-as-destiny, and upsets what a lot of conservatives see as the natural order of things. It promotes equality, not just of gays and lesbians to the rest of us, but between men and women in heterosexual marriages. And dismantling the patriarchal, autocratic model of the nuclear family is exactly what "traditional marriage" advocates are scared of.
To quote the article, "The lawyer arguing before the U.S. Supreme Court last week admitted that 'the main concern [for opponents of same-sex marriage] is redefining marriage as a genderless institution.'"
Maybe I have a dog in this fight after all.
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