This post is based on a comment I made at Pharyngula, which relates to the "all religions are fairy tales" billboard story I first saw described at Friendly Atheist.
The apparent objection to even the existence of the sentiment that religion is false strike me as particularly damning for the fundies.
- If their particular god really existed and really was a powerful being, what reaction would we expect such a sentiment as the one on the billboard to create?
Surely it would not be particularly troublesome. Mere background noise.
- If, on the other hand, the emperor has no clothes, but the religious billboard reader has a strong vested interest in maintaining their illusion that the emperor is clothed in gowns of the finest silk, what reaction would we expect to see?
Why, exactly the reaction we do see. Theists who can't stand the sight of a billboard like that give out the distinct impression that they don't actually, truly think God is real. They just want him to be true.
Look at it this way. If Santa is real, it doesn't matter if the rotten kid on the corner tells you he doesn't exist. It doesn't impact Santa at all, nor you - any more than him telling you he doesn't believe you live in a house can change your address (you can just shake your head and go about your business, secure in the knowledge that he's wrong). Maybe the kid on the corner's getting coal next Santamas, but there's no harm to you at all. The claim of his nonexistence would be mostly amusing, not offensive. Not a particularly emotive issue.
However, if Santa doesn't exist, then being told that he doesn't exist breaks the precious but fragile illusion that he does. That can be upsetting, because hearing the message means you're at least peripherally aware that the illusion is just that. If you're determined not to deal with the fact that Santa doesn't exist, then you can cover your ears and go "La-la-la" while running away... but it's clear to all around you that you in fact aren't at all sure he does exist. You just want him to exist, which is a whole other thing - the desirability of the existence of Santa Claus has no impact on the fact of his existence.
By now, you have probably read Ricky Gervais' deconversion story. (If you haven't had the pleasure, go take a look. I'll wait.)
What was it that convinced him God was made up? Was it his brother's simple, mildly skeptical question "Why do you believe in God?"
It was his mother's reaction to the question that proved to him that she didn't really believe in God - that his brother's very mild expression of disbelief had to be silenced because it was right.
Why seek to silence a merely mistaken opinion? People make mistaken claims all the time, and I don't see the fundies getting all in a tizzy over other simple mistakes. Where's the tizzy over the "mistakes" (which is far too generous a term, but anyway) that led to the War in Iraq? That cost many tens of thousands, probably hundreds of thousands of lives, and trillions of dollars (how much has it cost the people of Iraq? Who knows, but it's a lot). Where's the tizzy over mistakes that are actually real, and with demonstrably real consequences?
Mistaken opinions are not inherently offensive.
If the billboard was simply a garish mistake, they would not care so much.
The theistic panic-reaction to the billboard is in the same vein as Gervais' mother's reaction - they want discussion of the nonexistence of their magical sky-pixie silenced - not because the possibility of "non-existence" is obviously false, but because they worry, deep down somewhere they don't want to examine too closely ... maybe it's actually true.