In Britain, browsing internet porn is about to get a whole lot more complicated.

As of next year those who like to have an occasional self-fiddle while watching a saucy movie—that is, every male human being aged 13 and upwards—will effectively have to ask for permission from his Internet Service Provider (ISP).

Access to porn will be automatically blocked in the vast majority of British households—nine out of ten, the government estimates—meaning people who want to see this stuff will have to email or phone up their ISP and say: “Please turn off my filters.” Imagine how humiliating that will be. You might as well say to your ISP, “I like to wank while watching people have sex.”

It’s Prime Minister David Cameron’s idea. Convinced that the tsunami of porn on the internet is damaging young people, he has pressured ISPs to impose a pre-set parental control filter on all domestic internet connections.

These mandatory filters, which will come into effect early next year, will block pornographic fare. If you want porn, you’ll have to “opt in.” The government, without our say-so, is opting us out. One day next year Brits will wake up to discover that they no longer have access to certain images and words that they previously had access to.

The aim, says Cameron, is not to “lecture adults” about their web-browsing antics, but rather to empower parents, to allow mums and dads to keep their homes porn-free. “We are giving parents the opportunity to take a more positive role”, he says. “We are helping them with something they have asked us… to do.”

And what about those adults (let’s face it, mainly men) who have families but, every now and then in the privacy of their bathroom or study, also like to watch rollicking lesbians? How do they explain to their wives or girlfriends why they want these pesky “porn filters,” as absolutely everyone is calling them, switched off?

These “embarrassed husbands” will just have to “have a discussion” with their partners, Cameron says nonchalantly, as if he isn’t asking the men of Britain to do something many will find squirm-inducingly shameful. He’s effectively forcing British blokes to fess up about their fantasies, to make semi-public their private onanistic shenanigans.

There are so many things wrong with Cameron’s porn filter plan that it’s hard to know where to start.

First, as the free speech campaign group Open Rights points out, internet filters can be notoriously clumsy, often blocking stuff that isn’t actually pornographic or violent but which is merely “adult”: articles about smoking, advertisements for booze, etc.

Open Rights spoke with some of the ISPs who have agreed to impose a porn block in British households, and they admitted that other material might also get blocked—including “violent material, suicide-related websites, anorexia, and eating disorder websites.” So whole swathes of the internet are going to have a forcefield erected around them, and actual, sentient, fully grown adults will have to ask permission to penetrate this forcefield.

Second, and more importantly, Cameron’s plan represents an alarming intrusion into our homes, into our private lives, into the sovereignty of the family itself.

The imposition of filters on domestic internet connections won’t actually stop wily, web-savvy young people from seeing porn. Armed with smart phones and tablets, and aware that there are Wi-Fi connections pretty much everywhere these days, even the offspring of men and women who agree to allow ISPs to determine what bits of the internet their household can access will find a way to watch mucky movies. If those of us who were children in the pre-web 80s could find a way to source, store, and surreptitiously look at porno mags and crappy VHS videos of Italian women giving blowjobs, then today’s permanently connected youth will surely work out how to circumvent blocks and get their fix of filth.

But what these filters do is set a dangerous precedent: they will say it is okay for the government to behave as parent to their nation, as the stern, finger-wagging father to its citizens.

Cameron is in essence assuming the role of in loco parentis in relation to almost every household in Britain. But households are not only made up of children; they consist of—in fact they are run by—adults. And by forcing mandatory web filters on households Cameron is arrogantly overruling these adults, in the process denting both their rights to access online whatever the hell they want and their authority over their offspring.

It is one thing for the adults in an individual household to take measures to prevent their children from seeing porn; many do that, and good luck to them. But it is another thing entirely for ISPs, cajoled by officialdom, unilaterally to enforce child-protection measures on almost every home in Britain.

That interferes with private life, with parental authority, with the sovereign rights of individual families to determine, relatively free from everyday social mores and expectations, what their values and ideals should be. Using children as a moral shield, Cameron is sticking his foot in the door of family life, assuming the authority to switch off porn on everyone’s internet just as surely as our mums would switch off our TV sets when it got ridiculously late.

We need to challenge this top-down decree that all web connections should, by default, be child-friendly. What if Cameron decides next that erotic literature or fiery political tracts are also harmful to children and thus web access to them should be automatically switched off? No good can come of allowing politicians, in cahoots with ISPs, to tell the public what a “normal” internet should look like.