This is how the discussion went in Time:
You also said homosexuality was a public health risk. What evidence do you have to support that assertion?So, gay marriage is less like a napkin (as Santorum would have us believe) and more like uncontrolled spending. Gay families aren't forward-thinkers. We apparently don't care what happens to our kids (much less our nieces and nephews and neighbors). We just indirectly cause all sorts of mischief with our lack of purity, like lower divorce rates.
You’re talking about how it was compared to second-hand smoking? It was never this organization’s intent to say that if Bob is gay and Alex is not, Bob is going to be a health risk to Alex. I get asked all the time how same-sex marriage impacts my marriage. I say it doesn’t. But that’s the wrong question. How’s it going to impact the next generation? The reason we have a national debt is because you’re looking at yourself, not the next generation. With marriage, when you walk away from God’s design, there’s going to be serious ramifications. For us, it comes down to God’s design: one man, one woman. Anything outside that, we preach abstinence and purity. If everybody practiced that, we’d have a whole different culture today. A much better culture.
The sad part is that the right doesn't even attempt to claim that we negatively affect the broader culture when our families are safe and secure and existing. Gay marriage states have the lowest divorce rates and our kids do no better and no worse than kids raised in other families. But it doesn't matter. The big bad of marriage equality is just some nebulous unknown. Gay marriage is a bad thing. Evidence of its badness is that it exists. Beyond that, it really doesn't affect hets or het culture. But it will be. Quite possibly. Someday.