Public opinion on the gay marriage issue fascinates me as it never has before. There's been such a rapid shift recently that I am forced to wonder what's at the bottom of it.

Glenn Reynolds is a law professor in a pretty conservative state, and when he reports broad support for same sex marriage (more here), and when I see evidence of the numbers changing elsewhere, my restless curiosity is piqued, and so I must look for an explanation. Considering that homosexuals number in the single digits, the sea change in public opinion must be analyzed from a mainstream, heterosexual perspective, so I will attempt to do that.

People generally do not support a cause unless one of the following factors is present:

Homosexuals are not particularly loved, and most average Americans, while they wouldn't mistreat homosexuals, neither would they want to be seen as going out of their way to advance their "agenda." In fact, many heterosexuals are uncomfortable around the whole issue, and see it along the lines of "the less said the better."

To a certain extent, this discomfort sets them up to be equally uneasy with either the shrill pro-homosexual crowd or the anti-homosexual moral conservatives. It's common sense that if you're uncomfortable about something, then you don't want to hear about it pro or con. (Even less do you want your face rubbed in it.) Whatever makes the issue go away would therefore be something to support. Might gay marriage, by ending the rancorous debate once and for all, assist in making the issue go away? I think that's definitely part of it, but I think the sea change in support indicates something more than a desire to make an uncomfortable issue go away.

In any case, I don't think any broad-based love for homosexuals is at the heart of this shift in public opinion.

How about hatred of the moral conservative scolds who refuse to stop yelling about homosexuals? To illustrate (and to add a little color and flavor) let's take a choice recent quote from Dr. James Dobson, a leading foe of same sex marriage:

Barring a miracle, the family as it has been known for more than five millennia will crumble, presaging the fall of Western civilization itself. This is a time for concerted prayer, divine wisdom and greater courage than we have ever been called upon to exercise. For more than 40 years, the homosexual activist movement has sought to implement a master plan that has had as its centerpiece the utter destruction of the family. The institution of marriage, along with an often weakened and impotent Church, is all that stands in the way of its achievement of every coveted aspiration. Those goals include universal acceptance of the gay lifestyle, discrediting of Scriptures that condemn homosexuality, muzzling of the clergy and Christian media, granting of special privileges and rights in the law, overturning laws prohibiting pedophilia, indoctrinating children and future generations through public education, and securing all the legal benefits of marriage for any two or more people who claim to have homosexual tendencies. (Via Andrew Sullivan.)

I have zero tolerance for intolerance, and the contradictory nature of that drives me crazy sometimes. While I'm on record as opposing the government intrusion aspect of gay marriage (more here, here, here, here, and in countless other posts too numerous to list), I fail to see -- assuming for the sake of argument that gay marriage is "bad" -- how "good" (heterosexual) marriages are harmed by bad ones. It's really like saying that allowing people to eat what you don't eat harms your own dietary habits! If I eat pork, does that harm Muslims? If I eat McDonalds, does that harm the health nuts?

But I digress. I still must address the third possibility: Is there is something to be found in gay marriage which might be perceived -- whether consciously or unconsciously -- as conferring a benefit upon the straight majority? What might that be?

The more I think about it, the more I'm inclined to lean towards a trickle-down effect on freedom. Americans are over-regulated as it is, often feeling constrained, harassed, and hemmed-in at every turn. (More odious is the growing invasion of privacy in almost every area of personal life.) Homosexuality, while only directly affecting a small minority of the population, represents a quantum leap forward in the sum total of human freedom, because it's been so taboo for so long, and people are so traditionally uncomfortable with it, so that this loosening up inevitably must bring with it a corresponding sense of general tolerance -- of the kind that spills over in ways felt more than directly perceived. If privacy is invaded and freedom threatened, I think people naturally find it relieving to see a taboo cast aside. For who does not have something to hide? Something of which he might be ashamed? Something that he might not want the world to know about? And with homosexuals allowed to live openly as married couples, doesn't that take some of the heat off everyone else?

I can't be sure, but I suspect something of the kind. If I am right, we can expect more and more increased tolerance from sources generally not thought of or stereotyped as the tolerant sort.

Even "rightish outdoorsmen"?

Once the trickle-down effect gets started, it's rather tough to stop.