Sexual Liberationist Ideology

The term is not mine, but it's certainly an accurate and useful one.  Prof. Robert George uses it in this article which discusses the implications of legalizing same-sex marriage in New York state. 

The vote in New York to redefine marriage advances the cause of loosening norms of sexual ethics, and promoting as innocent — and even “liberating” — forms of sexual conduct that were traditionally regarded in the West and many other places as beneath the dignity of human beings as free and rational creatures.

Prof. George discusses the meaning of marriage in New York by saying,

What New York now offers its citizens is “marriage” in name only. In reality, it doesn’t give marriage to same-sex partners — the nature of marriage makes that impossible, just as it makes it impossible to offer marriage to parties of three or more persons in polyamorous sexual partnerships. Rather, it takes away the legal recognition of marriage — a comprehensive union of persons ordered to having and rearing a family. 

He goes on to explain how sexual norms will erode further.

Because these domestic partnerships are not actually marriages, despite the appropriation of the label; there is no intelligible basis in them for the norms of monogamy, exclusivity, and the pledge of permanence that structure and help to define marriage as historically understood in our law and culture. 

 
Prof. George's remarks put in perspective the New York Times article I referenced here.  In fact George cites the article himself and concludes

On sexual-liberationist premises, there is no reason (apart from the subjective tastes of this or that particular set of partners) for “marriages” to be monogamous and demand sexual fidelity.

There's much more good reading in this piece.  The culture wars continue.