Yesterday's twist in the Ipswich murder investigation was the allegation that a senior police officer was a client of two of the women. Whether true or not, the mere suspicion was shocking enough to grab the front page. And this is the reason why we are failing all women desperate enough to sell themselves on the streets.

There has been much self-congratulation recently that we, as a society, have grown up about the sex trade. We are doing so well at “humanising” the women murdered in Ipswich that, although prostitutes, they have also been shown to be someone’s daughter, mother, or wife. It is not enough. We will not have begun to understand the problem until we start humanising prostitutes’ clients too. Let us stop thinking of these men as just “kerb crawlers”, they are someone’s husband, father, or son. Quite possibly yours.

Most of you will recoil at that idea, as I used to. But for all the talk of prostitutes as marginalised, their stock in trade is being visible. It is the men who stay hidden, gliding past in their dark cars. We have little sense of who they are, and less inclination to wonder. The sex industry, like the meat industry, is full of unpleasantness that we do all we can not to think about. When pushed, we might say the punters are “old”, or “lonely” or the “ dirty mac brigade”.

I was looking for dirty macs the day I spent in the company of 30 kerb crawlers, and there were quite a few, but, well, it was raining that morning. We had arrived at a rehabiliation programme for men who had been arrested for using prostitutes in Washington DC — the delightfully named “John School”. As in several American states, the city waived a conviction if the “johns” underwent a day of admonishing lectures from doctors, psychologists and ex-prostitutes. For me, my education was all in the first five minutes.

What, I thought, do these seedy creeps look like, prised from the safety of their cars? The first to take his seat in the classroom was a tweedy government policy adviser, who began reading Harvard Business Review to kill time. Next to him a group of young men, some of them teenagers, broke the ice — it was an unusual social occasion for everyone — by bantering about mobile phone ring tones. A rabbi — the school had seen clerics of every faith — sat next to a white-haired father of two, fiddling with his bag. It contained a packed lunch his wife had prepared for him, believing he was going fishing. Truly, all male life was there. I suppose I had always thought myself a good judge of character: kerb crawlers were other people, not the men I knew and liked. Yet I found myself, at a coffee break, flirting with an attractive young web designer and thinking he would be a nice guy to fix up with my friend on a blind date. Then I knew that certainty in my life had gone.

For the women who worked on the John School programme, that realisation had come long ago. When I asked the motherly administrator if her work had changed her view of men, she laughed: “Yes, I don’t date them anymore.”. The risks were too high, emotional and venereal. True, she was jaded by her job, but the statistics in Britain show one in eleven men has paid for sex, a near doubling in ten years. The National Survey of Sexual Attitudes and Lifestyles, which interviews more than 10,000 British adults, found that men rich or poor, black or white, middle or working class, were equally likely to use prostitutes. Oh, and being married or living with a girlfriend didn’t stop them either. Sound like anyone you know? “Women have no idea,” said the lady at John School. “They think their man won’t do anything like this. And I bet you think the same.”

So what, you may think, isn’t it understandable if a woman does not care to contemplate her man's weakness for whores? But it does matter. In a book she wrote after reporting on the hunt for the Yorkshire Ripper, Joan Smith argued powerfully that the reason Peter Sutcliffe remained at large for so long — and survived nine police interviews — was that detectives were looking for a bogeyman. They had convinced themselves he was probably a loner and a weirdo. One senior officer said: “If we had 20 or 30 suspects in one room we would know very quickly which one was the Ripper.” In fact he was just a local bloke, a married man who, said Smith, shared the police’s “background and attitudes to a remarkable degree”. An acceptance of this would have saved a lot of lives.

Of course most men who visit prostitutes are not there to kill them, but a similar principle is at work. We distance ourselves from the problem by distancing ourselves from them. The consequence of this? Vulnerable women suffer. Government policy on prostitution is as blinkered as the most wilfully ignorant wife: the so-called “shake-up” this year amounted to some noises about a crackdown on street prostitutes, the easiest of targets.

I am not so naive as to think men will not always use prostitutes. But if we want to improve conditions for the women, we have to take a little responsibility, and it must be collective responsibility. It is not the fault of the girls. It is not them, it is us.

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