William Saletan has a very silly article over at Slate this morning arguing that gay marriage shouldn't be threatened by the "hyperventilating conservatives" who see it as a gateway to polygamy.  His reasons?  That one on one relationships conform better to "human nature" and polygamy inherently unstable due to the jealousy factor. 

If you're going to make the "human nature" argument one might extend that to gay marriage as well, seems to me, but the argument that polygamy is inherently unstable is completely specious.

Muslims have been practicing polygamy for 1400 years and Fundamentalist Mormons have been practicing polygamy continually in this country since the 1830s (that's 175 years).  How much longer must they carry on in order to prove their stability?    He claims,

"Women shared [note the past tense - RB] husbands because they had to. The alternative was poverty. As women gained power, they began to choose what they really wanted. And what they really wanted was the same fidelity that men expected from them.

"Gays who seek to marry want the same thing. They're not looking for the right to sleep around. They already have that. It's called dating. A friend once explained to me why gay men have sex on the first date: Nobody says no. Your partner, being of the same sex, is as eager as you are to get it on. But he's also as eager as you are to get it on with somebody else. And if you really like him, you don't want that. You want him all to yourself. That's why marriage, not polygamy, is in your nature, and in our future."

Gays may be seeking relationship stability through marriage, but it is unlikely they will find it there.  Meanwhile, polygamy will continue so long as there are people who believe it to be divinely sanctioned.