All I seem to be doing at the moment is arguing about Adam Johnson. I bickered about him over dinner at a friend’s house. I rowed about him in a poker game, where it’s bad form to have a difference of opinion about anything other than the likely outcome of a sporting event.

At a birthday party in a pub, I quarrelled about him so bitterly that my opponent and I had to have a hug at the end of it. A redemption hug! In the middle of a birthday party! Sober!

You know, presumably, who Adam Johnson is? He’s that footballer who’s waiting to be sentenced for sexual activity with a 15-year-old girl.

Chances are you think he got a bit unlucky; the public shame and sacking are punishment enough and a few months or a suspended sentence would do the job. That’s what everyone I meet seems to think.

Me, I hope he gets 10 years. As the old joke about the beekeeper goes: f*** him.

Questions of what the girl said to Johnson on Facebook or WhatsApp, how “only just underage” she was, or looked, or who “made the running”, are as irrelevant to me as the weather on the day.

At the birthday party, as I snarled about the ghastly things I hoped would befall that itchy-fingered dribbler during a long spell in prison, my friend (a respected author) said: “Rhetorically, you’re leaving yourself nowhere you go. You’d be saying the same things if he raped an eight-year-old.”

He’s right. I would. And I’m fine with that. I am bored to all hell with the “could be worse” argument. It has hamstrung us as a society for too long; it’s a rhetorical game of no practical value.

The reason I’ve been getting into these rows, I think, is that my friends are surprised I take such a hard line on Adam Johnson and I’m frustrated that they don’t. It’s not just a difference of opinion, it’s a mutual lack of understanding.

When I speak about Adam Johnson as a child abuser, they think I’m on the side of the 21st-century’s bad guys: the absolutists, the pullers-down of statues, the Twitter mob. I would usually be on the side of nuance and complexity, grey areas and a peaceable approach. But not here.

Rape and sexual abuse have been grey areas for hundreds of years. Not so bad if it’s your wife. Not so bad if it’s a prostitute, a flirt, a drunk. Not so bad if they’re nearly 16.

And where has all this sophistication got us? How’s it going, this nuanced approach? There is just so much suffering. So many bruised souls, broken hearts, damaged psyches, awful memories. There’s barely a woman alive who hasn’t had some experience of sexual fear, however tiny or transient. It’s embarrassing how universal that is. There’s barely a girl on Earth whose sexual awareness started with her own desire, rather than the creepy stare or touch or comment or otherwise intrusion of a third party. Who knows what that does to us?

So what do we have to fear from zero tolerance? Losing the happy status quo? Hardly.

It’s like drink-driving. Decades of relativism on that issue were probably fair to nice folk who were driving home after a glass or two and meant no harm. But a lot of people died. So now we have an absolutist approach and a lot of mildly tipsy drivers have been very harshly punished – perhaps unfairly in the immediate, individual sense – but far fewer people die.

My liberal, intelligent male friends are arguing with me on Johnson because they think it’s not that bad to have sex with a 15-year-old – just like my father didn’t think it was bad to drive after a bottle of wine. I am not a better person than my father was. But I am less likely to kill someone.

By that logic, we should be eager to try an absolutist approach to having sex with children. Let “a child” be anyone who is under the age of consent by so much as an hour. We’ve got to define it somehow and that’s how.

If your victim is 15 and you get the same punishment as someone who abused an eight-year-old, I don’t care. If this child performed the dance of the seven veils, beckoning and pouting, and you get the same punishment as someone who jumped out of the bushes, I don’t care. Unlucky. Let God make those moral distinctions. It’s too subtle for humans; we’ve failed to make it work.

It would take only one generation of “zero tolerance” for the thinking to shift and it become simply preposterous – inconceivable – for anyone who expects to be considered normal to have sex with a minor. They’ll make it their business to know if someone’s underage and leave them alone.

The truly ill, of course, will keep on abusing, just like some people will always drive drunk. But the goalposts will shift in ordinary people’s thinking and vast amounts of suffering will be spared.

The fact that Adam Johnson might not be “a monster”, but actually sort of normal, is the very point. It’s the “sort of normal” people who can modify their behaviour. Our concept of normality has caused so much misery and pain; it has to change. And if Adam Johnson gets 10 years, maybe men will stop having sex with teenagers.

Maybe they’d only stop through fear. But that’s a start. They would not have become better people, but they would have become less likely to destroy a child.

I understand why I disappoint my liberal, intelligent friends when I reject their attempts at nuance. But I hope they understand my own frustration: it’s like they don’t want the world to change.

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