While Emily Post or Miss Manners might not phrase it that way, “Don’t be a dick” is pretty much the first rule of etiquette. That is to say, the first rule of dealing with other people in a world that’s populated by animals that have evolved to become intelligent, conscious social beings. For an atheist, this means not treating people as inferior to yourself, even if you think their worldview is distinctly so.
If you’re an atheist, there’s a good chance you’ve encountered some smug Christian tossing out the Bible verse about how “the fool says in his heart, ‘there is no God.'” It’s possible for atheists to be just as smug and condescending and obnoxious toward non-atheists.
Does that mean that activist types like Richard Dawkins are violating this rule? I have no idea — I’ve never met Dawkins, let alone seen him in a social situation. Writing a book — or a blog post — isn’t a social interaction. You write what you want to write, people read it or don’t read it, and think whatever they want to think. It has nothing to do with etiquette, or manners, or social behavior.
One could argue that strident atheism affects the social climate (as does strident religion, or strident anything, or refraining from stridency)I’ll let PZ Myers and Greg Epstein discuss the finer points of the big picture. But etiquette isn’t about the overall social climate, it’s about specific interactions between individual people.
Think of it this way: In most situations, hitting someone in the face is considered rude (to say the least). In a boxing ring, hitting someone in the face is pretty much the goal. If you’re in an arena (metaphorical or literal) where the purpose is to demonstrate that your opponent is wrong, it’s not necessarily rude to make that demonstration in such a strong manner that not only is it clear that your opponent is wrong, but that he’s an idiot.
But in social situations, we try to be nicer to people, no matter what we may privately think. It’s not polite for a Catholic to tell a Protestant that he’s going to hell because he never ate a cookie and washed it down with some wine, even if the Catholic (like many, but not all, Catholics) truly believes that to be true. Likewise, it’s not polite in a social situation for an atheist to tell a non-atheist that he’s got a nonsensical, self-contradictory and ultimately absurd view of reality, even if that’s what the atheist truly believes.