By way of Andrew Sullivan we come across this article on the gay marriage debate:
- How to get 63% of Americans to support gay marriage (maybe) (FiveThirtyEight.com)
In it, Nate Silver applies the notion of negative liberty (“you have the right to <foo>” means “no-one’s allowed to stop you from <foo>”) to the debate. Rather than ask “why shouldn’t the government allow gays to marry?”, he prefers (as, having come across it, do I*) “why should the government be allowed to forbid gays from marrying?” Starting from the notion that everyone starts out with an equal set of inalienable rights, Silver asks why we should grant government the power to prohibit Alan and Bob from getting married, but not Carol and Dave. (Or rather, he suggests that equal-rights advocates should frame the question this way — but I’ll take this farther if I please.)
And it turns out that if you frame a polling question in this particular way, as Gallup and USA Today did recently, you get a very different set of responses. [chart elided] When USA Today asks whether gay marriage is a private decision, or rather whether government has the right to pass laws which regulate it, 63 percent say it’s a private decision. This contrasts significantly with all other polling on gay marriage. The highest level of support gay marriage has received in the more traditional, positive-rights framing is 49 percent, from a ABC/Washington Post poll in late April.
A lot of the frustration I come across from conservatives on the gay marriage debate (those that’re against it, that is) stems from the perception that “the gays” are asking for special rights, special treatment, and/or special consideration. This is, in essence, absurd: if the Bill of Rights means what it says on the tin, then asking for the right to get married is like asking for the right to eat breakfast. But asking for the right to get married is precisely what many equal-rights advocates do:
[E]ven though gay marriage had already become — however briefly — the law of the land in California, that wasn’t how the debate unfolded on Proposition 8. Instead, look at what Equality California said on its website at the time:
Every Californian should have the choice to marry the person they love. It’s a personal and fundamental freedom guaranteed by the California Constitution.
[...]
What if Equality California had instead said this:
California’s government should not have the right to interfere with the decision of two loving adults to get married. It’s a personal and fundamental freedom protected by the California Constitution.
If you keep begging to keep something that’s rightfully yours, sooner or later whoever you’re begging is going to get the idea that they have the authority to take it away. (This is, in a nutshell, why the positive-liberties framing drives me up the fucking wall.)
——
* I’m a bit embarrassed that this didn’t occur to me independently. I guess I haven’t hit libertarian perfection yet.

I think it should really be discussed in terms of licensing instead of marriage. It wouldn’t make any more sense to refuse to give gays fishing licenses because someone’s religion is opposed than it does to refuse to issue them marriage licenses.
Given the way BC refuses certain fishing licenses to people with the wrong background (want to go whaling? You’d better be the right kind of First Nations), I don’t share your optimism. I do like the idea of separating the contract-law component of marriage (in which the government has some interest, at least for enforcement) from the religious/traditional part (in which the government has no business whatsoever), which is where I think you’re going with this.
The non positive-liberties framing (sorry, couldn’t think of a clearer way to put it) also puts to bed the whinging by some that opening the door for gay marriage must also open the door for polygamy. Or marrying amusement park rides.
I think that positive-liberties framing is the problem behind a lot of bad law. The idea that /everyone/ has a god-given right to whatever thing a law or regulation might open the door to is deeply flawed. Responsibilities go along with rights (except, maybe the right to breathe). As a society we need to get back to recognizing this or well all end up in identical, goverment-issue, padded cells eating soylent green.
This is a neat, clean way to express something I’ve been getting worked up about in other debates: having the right to do something doesn’t mean it’s a decent thing to do. Positive rights imply some sort of endorsement from the government (or whoever’s granting the right) — “it’s okay for you to do this”. Negative rights don’t, they simply imply disinterest (“it’s none of my business; I’m not going to stop you”).