Let's get to work on undoing the Supreme Court's mistake. Despite today's Supreme Court ruling, let's remember what hasn't changed. We, including the government, still have good reason to distinguish between opposite-sex and same-sex relationships and, therefore, not place them together under the classification of marriage:
- Opposite-sex relationships still promote the unity of the genders in a way that same-sex relationships don't. Since the genders are so different, and their living together in harmony is so important, we have good reason to acknowledge a distinction between a relationship that's so effective in uniting the genders and a relationship that isn't.
- Opposite-sex relationships still have a potential that same-sex relationships don't have to produce biological offspring. Even if an opposite-sex couple is undecided about whether to have children, has decided not to have any, or is infertile, the potential for having children remains. We occasionally hear of a woman in her sixties or seventies having a child, though that's rare. Given how important biological offspring are to a society (e.g., the problems we're seeing in parts of the world with low birth rates), the potential for offspring is important even if a couple doesn't currently expect to have any children. And drawing the line at gender differences (distinguishing between opposite-sex and same-sex couples) would be a more efficient way to handle this issue than doing something like running fertility tests on every couple or trying to figure out an age limit for marriage.
- Opposite-sex relationships provide a significantly different environment in which to raise children. I deny that the differences between men and women are only anatomical, but, even if they were, that distinction alone would give us sufficient reason to distinguish between opposite-sex and same-sex parenting. It's more effective to teach children how to live with their own anatomy and how to live with somebody of the other gender in the setting of opposite-sex parenting. And if you believe that gender differences go beyond anatomy, as you should, this distinction between opposite-sex and same-sex parenting becomes even more significant.
- We have good religious grounds for distinguishing between opposite-sex and same-sex relationships. See our material in the archives here on the evidence for Christianity, for example. That evidence gives individuals, families, churches, etc. good reason to think that same-sex marriage is unethical. Even at a governmental level, religious considerations should be taken into account. Our system of government is founded on the religious notion that we're endowed by our Creator with rights. We print "In God We Trust" on our currency, open sessions of government with prayer, etc. To turn around and suggest that we can't have any religious motives for doing what we do at a state level would be irrational and inconsistent. Even where people don't explicitly articulate a religious motive, they often have one. Even political liberals often oppose racism, support helping the poor, oppose the death penalty, etc. on a religious basis. Voters frequently vote with religious motives, and the idea that legislators don't do the same is implausible. Religious motivation has been part of our political system from the start. The more secular modern definitions of separation of church and state are just that: modern definitions that are competing with other definitions, including ones that are older and more reasonable. If you want an argument that Christians should oppose homosexuality and same-sex marriage on religious grounds, see Robert Gagnon's material, for example.