When people say the "law is an educator," that's true, but it doesn't go far enough. In this case, the law is an arbiter of reality: Who is really married? Who is really divorced? Who is having an out-of-wedlock child? Who, for that matter, is committing adultery?
The law's power to name reality matters.
By the way, I do understand that is why the "name" matters to gay-marriage advocates. That's what makes this battle difficult to compromise. But all I ask, of the intellectual class at least, is they stop saying therefore that the defintion of marriage in law (which matters so much to Adam and Steve) won't matter at all to anyone else.
I would add one thing: the power to name, in effect, controls how we think. We formulate our thoughts in words. When words become corrupted, or ambiguous, our thoughts change as well.
To give just one example, it used to be a fairly unexceptional statement to say, "Kids need mothers and fathers." That idea now has to be accompanied by an asterisk: kids need mothers and fathers, unless one of their parents is gay, in which case, having an opposite sex parent is completely optional. The plain vanilla thought, kids need mothers and fathers, without qualification, without apology, is becoming more and more difficult to formulate and state.