Dr Tim Stanley is supposedly an “historian of the United States”. In this article he writes about a comic book store called “Porn Star Karaoke”. He either means Sardos in Burbank or the late Bill Liebowitz’ enterprise Golden Apple on Melrose and LaBrea. Sheeesh.

Stanley writes on www.telegraph.co.uk – A few years ago in Los Angeles I went to an event held at the back of a comic book store called Porn Star Karaoke. It’s not as sexy as it sounds. About half a dozen porn actors from the “golden age” of the industry got together to sing Eighties power ballads dressed up as superheroes – the sort of thing that would cause a big stir in any other city but is just another wet Tuesday night in LA.

The audience comprised about half a dozen specially invited “fans” and me and a pal sat in a corner eating pizza and drinking beers. The singing wasn’t very good – although I recall a rendition of Take My Breath Away by a near naked Wonder Woman that made a couple of heavy breathers stand to attention.

The whole thing was a sad coda for the “mainstream” division of the porn industry that pretty much collapsed eight years ago, its former stars now reduced to cabaret and special appearances (do they do children’s parties? Probably, this is California we’re talking about). Now Fox News reports that the business is being kept afloat by celebrity sex tapes – the equivalent of a TV network relying on the novelty value of Dancing With the Stars to keep ratings up. Why are things so bad? Two reasons: the internet and disease.

It’s often presumed that the internet is porn’s best friend – and filth certainly accounts for about 12 per cent of all websites curently available. But while the internet has undoubtedly increased supply it hasn’t lifted the profits of production. On the contrary, it’s killed off the dirty cinemas and naughty DVDs that generated hard cash. The performers at the Porn Star Karaoke were all 30-somethings who rode the wave of the late-90s, early-Noughties DVD boom which was often centred on personality: actors would build up fan bases and could demand high fees if it was known that their face/genitalia could push up the price of a DVD.

With the arrival of the internet and the ability to speedily download cheap trash from all corners of the globe, their bargaining power collapsed and they found themselves either doing low-grade stuff for scraps or forced to retrain. As Gloria Swanson put it, “I am big. It’s the pictures that got small!”

Salon explains the business crisis thus:

Most commentators identify five factors contributing to the predicament now facing the commercial porn industry: (i) the widescale pirating of copyrighted porn and its illegal resale and posting by opportunistic websites; (ii) the ease of producing do-it-yourself (DIY) amateur porn videos; (iii) the enormous increase of “free” porn sites; (iv) the resulting change in business economics; and (v) the ongoing recession with cuts discretionary spending, especially among a certain sector of the male audience.

This restructuring has led to the closing of many commerical porn companies and cuts in jobs and fees to porn workers. Not unlike other once-analog media industries – e.g., newpaper, magazine and book publishing – porn is struggling to make the transition to digital online publishing.

So the wages of sin are falling. Of course, the old “porn houses” would insist that they’ll be missed – that they operated some degree of quality control that benefit their workers and society as a whole. The producers, financiers and actors all knew each other and something akin to a “community” existed, offering support and a certain degree of care to those who worked within it.

By contrast, the amateurs who are taking over the internet are probably more likely to be exposed to sexual abuse, poverty and disease. They’re also more likely to engage in barnyard action and other assorted depravities, the kind of thing that the old industry avoided.

As with any drug, the greater availability and variety of online content has created a new breed of addicts who require a bigger and more plentiful fix every time they turn on. Recall Randy Marsh in South Park explaining to a friend that he can’t relieve himself without access to the internet because its shocking content has left him deadened to ordinary stimuli: “I need the internet to jack off. I… got used to being able to see anything at the click of a button, you know?

Once you jack off to Japanese girls puking in each other’s mouths you can’t exactly go back to Playboy!”

But let’s not get too sentimental about the old production houses. All aspects of the sex industry are innately dangerous – for while we would love to imagine that we live in an age of consequence-free pleasure, the reality is very different.

A shocking outbreak of HIV has caused the adult film industry’s trade association to try to impose a moratorium. The stories about what went wrong are tragic and graphic, and reveal a business that actually cares little about its employees.

I’m not exaggerating: it doesn’t give a damn. We are repeatedly told porn is something that people choose to engage in – that it’s a safe and pressure-free environment. Cameron Bay’s account of how she contracted HIV from a fellow performer who was actually bleeding on set says different. Filming at a public bar, she describes a scene out of the last days of Rome:

There were up to 50 people in the room with us. And we were laying on top of them. And they were touching inappropriately. It all happened so fast. I didn’t realize how unsafe it was until I saw the pictures … You’re on a whole other level when you’re doing something so extreme.

Performer Derrick Buts told how he worked in porn for just four months and still managed to contract chlamydia, gonorrhea and herpes – before finally succumbing to HIV. Patrick Stone told reporters that he’d been tested positive for HIV and advised his employer, yet he was still asked to do filming. Most of these people had surprisingly brief careers in porn before disaster struck. It’s not unreasonable to conclude that they were lied to about conditions and consequences.

Rather than facing up to the truth about human nature, Western society prefers to replace old lies with new ones. We used to lie to ourselves that no one looks at porn and that if you do your eyes will fall out. Now we lie that everyone looks at online porn (they don’t, and of those who do some 80 per cent are men), that it has no side-effects, that it’s 100 per cent safe to perform in, and that it’s really just a business like any other.

In some senses, that last proposition is right: it’s subject to the whims of market forces and changing technology that affect newspapers and book publishers. But in so many ways it is something uniquely dangerous and potentially lethal. It desperately needs far tighter regulation and a more healthy degree of public shunning. Things like filth are usually taboos for a reason.