WHAT does the neighbourhood pervert look like?
Now we know. He's not dirty and seedy. He's not homeless. He's young. Clean-cut. Ordinary. He wouldn't be caught dead in a dirty-old-man trench coat.
He might be, like former A Current Affair journalist Ben McCormack, a volunteer lifesaver who spends his weekends training nippers. He might, like former American politician Anthony Weiner, be married to a beautiful and highly successful woman whose glittering career matches his own.
And so now we know.
Pederasts and child abusers aren't creepy looking outcasts. They're successful men at the heart of commerce and society.
You probably know a couple, consider them friendly acquaintances. I certainly did.
I'd encountered ACA's McCormack a few times professionally, and found him polite, open, friendly and enthusiastic in person. He was close friends with a couple of people I respect enormously, although he had also offended another friend with some of his social media rants about world politics. He was someone, I thought, who obviously had an intense and bitchy side, but who seemed keen for everybody to like him.
And now we know he was secretly discussing the sexual abuse of children online, referring to himself as a "proud ped" and "proud b(oy) lover". He admitted in his online conversations to having links to child-abuse material - the kinds of pictures and videos for which young bodies have been exploited in the most stomach-turning ways.
I did not sense anything even slightly sinister about the guy.
And if I didn't feel any unease - a grown woman who has spent a couple of decades in the relatively worldly profession of journalism, and who has encountered plenty of sexual offenders through my work - how could any child be expected to be wary of him?
McCormack pleaded guilty this week to two child pornography offences after his online conversations were intercepted by police.
Just a day later, former US politician Anthony Weiner was sentenced to 21 months in prison for transferring obscene material to a minor - specifically, pictures of his genitalia to a 15-year-old girl in an online chat.
The urbane, successful nature of these people is exactly what makes them frightening.
And they are the reason, I think, why modern parents are 100 per cent right to keep their children close.
"Oh, it's such a shame parents don't let their kids walk to school alone any more," you often hear someone say.
Or: "When we were kids we just roamed the neighbourhood. Mum used to kick us out the kitchen door and say 'Come back for dinner'."
Yep. And now we know that in that unsupervised time, our friends, relatives, schoolmates were being abused - not by some freaky-looking guy they should have avoided, but by the local soccer coach, the maths teacher, the next-door kids' dad. Someone utterly unremarkable. Someone children could never, ever know to avoid.
There's a common idea that our children are living in an incredibly dangerous world, and that child sexual abuse is more rampant now than it was in the past.
I seriously doubt it. The internet has provided these creep shows with a forum and a platform to share material - but I think their tendencies are nothing new. Paedophilia has been with humankind, I'd hazard, since we crawled from the swamp and stood up on two legs.
Some adults will take sexual advantage of the small and weak.
Those victims may, as adults, grow up to themselves become perpetrators.
That's the nauseating cycle of sexual abuse.
So here's the difference: today there is no excuse for being ignorant about the risks children face.
Thanks to the slow breakdown of the old taboos about admitting to being a victim of sexual abuse, today's parents must know that the dangers to their children are real.
In previous generations, the taboo protected offenders. It meant parents could quite reasonably have been naive about the extent to which their children were vulnerable.
Now we cannot claim naivete or ignorance as a defence. We probably all know an Anthony Weiner or a Ben McCormack.
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