"Every possible form of interaction between an adult and a child is perceived as yet another opportunity for child abuse."

Frank Furedi, professor of sociology at the University of Kent and author of Paranoid Parenting: Why Ignoring the Experts May Be Best for Your Child has an article at PJM on the paranoia over photographing children:

The assumption that pictures represent a significant threat to children has acquired a fantasy-like grotesque character. We rarely dare ask the question: what possible harm can come from taking pictures of children playing soccer? Dark hints about the threat of evil networks of pedophiles are sufficient to corrode common sense. Tragically, what the dramatization and criminalization of the act of photographing children reveals is a culture that regards virtually every childhood experience from the standpoint of a pedophile.

Every possible form of interaction between an adult and a child is perceived as yet another opportunity for child abuse. In a roundabout way society has normalized pedophilia. The default position is to always expect the worse — and therefore children should be placed in purdah.

Take a look at the comments too, they are illuminating and some commenters explore child abduction numbers; for example, here is an article from Slate that sheds some light on how many kids are really abducted--only 115 were "stereotypical kidnappings," defined in one study as "a nonfamily abduction perpetrated by a slight acquaintance or stranger..."