Ramesh, I hardly recognize my argument in your synopsis of it. I did not write the American Conservative piece in order to argue that “the conservative movement has been ‘crippling itself’ by alienating atheists and agnostics who oppose same-sex marriage,” as you phrase it. Yet by placing so much weight on one phrase from my article, you make it seem as if the whole essay was about same-sex marriage. I listed several conservative values held by non-religious conservatives; only one of those was a belief that children raised by their married biological parents are in the optimal family structure. My point was to show that non-believers can arrive at standard conservative positions, such as support for personal responsibility and private initiative, through non-religious means. I was not claiming that “opposition to same-sex marriage should be a central conservative cause,” as you put it.
But since you make my statement about marriage the central theme of my piece, let me clarify: I would count among the less wise alternatives to marriage between biological parents the legion single mother households that liberals once celebrated as the triumph of feminism. Even liberals, however, have begun to lose their enthusiasm for single-mother families, based not on Biblical revelation, but on the irrefutable empirical evidence that children in such households face far higher odds of gang involvement, school failure, and teen motherhood themselves. My guess is that there are a lot of non-religious people who object to same-sex marriage on the ground that it further weakens the belief that children need their mother and their father to enjoy the best chances for success in life.
My real point in writing, however, was to say that reason and a commitment to evidence provide ample grounds for leading a moral, responsible life. Unfortunately, I have heard too many leading Republican pundits suggest the opposite.