"I know it when I see it."
You think you do, but you don't.
I have 6 kids, aged 1 to 19, and my concern is that they not be exposed to porn, or exposed to anyone who thinks exposing them to porn is a good thing.
It *is* about the children. There is *no* hidden agenda.
Next thread like this you'll want to start arguing that bogus "hidden agenda" nonsense earlier; it will have more faux credibility that way.
If you rely on others to protect your kids, you have lost the battle.
Why not teach them your values such that they do not view porn in librarys, their friends homes, tv shows, book stores or movies? And if they do happen to get exposed to it, they know how to properly respond? Is it really that diffcult? Are your values so unsuportable that they require a Nanny State to protect them?