Via Joe Carter , I see that the family scholar Elizabeth Marquardt speculates  about how our society is going to end up embracing, or at least talking seriously about embracing, polyamory and plural marriage. Excerpts:
The debate about legal recognition of polyamorous relationships is already well underway. A major report issued in 2001 by the Law Commission of Canada asked whether marriages should be “limited to two people.” Its conclusion: probably not. A British law professor wrote in an Oxford-published textbook that the idea that marriage meaning two people is a “traditional” and perhaps outdated way of thinking. Elizabeth Emens of the University of Chicago Law School published a substantial legal defense of polyamory in a legal journal. She suggested that “we view this historical moment, when same-sex couples begin to enter the institution of marriage, as a unique opportunity to question the mandate of compulsory monogamy.”
Mainstream cultural leaders have also hinted at or actively campaigned for polyamory. Roger Rubin, former vice-president of the National Council on Family Relations–one of the main organizations for family therapists and scholars in the United States–believes the debate about same-sex marriage has “set the stage for broader discussion over which relationships should be legally recognized.” The Alternatives to Marriage Project, whose leaders are featured by national news organizations in stories on cohabitation and same-sex marriage, includes polyamory among its important “hot topics” for advocacy. The Unitarian Universalists for Polyamorous Awareness hope to make their faith tradition the first to recognize and bless polyamorous relationships. Meanwhile, a July 2009 Newsweek story estimates that there are more than half a million “open polyamorous families” living in America. Nearly every major city in the U.S. has a polyamory social group of some kind.
Andrew Sullivan  today linked to a personal account of a young man who came to call himself a polyamorist after a girl he met invited him to fly to her home to have sex with her, with her husband’s consent. What’s interesting about this is how the man’s conscience kept trying to stop him. For example:
“Is your husband really ok with this?”
“Do you want to ask him?” she asked.
“No!” I quickly exclaimed.
The whole thing just felt odd. I tried to put my finger on it, but I couldn’t. Eventually I concluded that my feelings of weirdness grew purely from the fact that she was married and what that word meant to me. It didn’t make a whole lot of sense to expect someone else to conform to my notion of what a marriage was, so my reticence was not from any concern that could be considered rational. And as someone who has made a career out of telling people that emotional responses should not take precedence over rational ones (and as someone who likes sex with attractive, super nerdy women), it did not take Christina long twisting my rubber arm until I agreed.
At least once more, when confronted by her husband, he balked. It felt wrong. But the husband talked about his girlfriend, and how cool polyamory was, and, well, that was that. And now:
I’ve learned a lot from Christina and Chris, but chief among them is that I am polyamorous and would have been much sooner if not for a bunch of wonky societal myths. And so I write blog posts like this, because that’s why we come out. We come out to normalize something we think are awesome in order to dispel those myths.
We’re going to be seeing a lot of this, I bet. People who have nonjudgmental attitudes about sex deciding that the only thing keeping them from violating taboos is fear. And when that is conquered…
You may recall Justice Scalia’s dissent in Lawrence vs. Texas , when he observed that:
State laws against bigamy, same-sex marriage, adult incest, prostitution, masturbation, adultery, fornication, bestiality, and obscenity are likewise sustainable only in light of Bowers’ validation of laws based on moral choices. Every single one of these laws is called into question by today’s decision; the Court makes no effort to cabin the scope of its decision to exclude them from its holding.
… The Texas statute undeniably seeks to further the belief of its citizens that certain forms of sexual behavior are “immoral and unacceptable,” Bowers, supra, at 196–the same interest furthered by criminal laws against fornication, bigamy, adultery, adult incest, bestiality, and obscenity. Bowers held that this was a legitimate state interest. The Court today reaches the opposite conclusion. The Texas statute, it says, “furthers no legitimate state interest which can justify its intrusion into the personal and private life of the individual,” ante, at 18 (emphasis addded). The Court embraces instead Justice Stevens’ declaration in his Bowers dissent, that “the fact that the governing majority in a State has traditionally viewed a particular practice as immoral is not a sufficient reason for upholding a law prohibiting the practice,”ante, at 17. This effectively decrees the end of all morals legislation. If, as the Court asserts, the promotion of majoritarian sexual morality is not even a legitimate state interest, none of the above-mentioned laws can survive rational-basis review.
Scalia has shown how and why, when gay marriage comes before the Supreme Court, a majority of justices will rule it to be a constitutional right. How could they not, given Lawrence? And having so ruled, what rational basis is there to deny polyamorous, er, entities legal recognition? By then, though, it may not even be controversial, given the progressive liberalization of attitudes toward sex.