The Edward Snowden documentary Citizenfour opens in UK cinemas on Friday, putting the dangers of surveillance squarely in the public eye. But Laura Poitras’ film isn’t the first time that an artist has explored the threat that technology poses to privacy. John Cheever did it, too, in 1947.

Everybody knows that privacy is in trouble. We know that we are being monitored, we agree that it is disturbing – and yet we continue with our online lives regardless. Why are we so nonchalant, so blithe? Why don’t we care?

We need a fable about privacy. A gothic tale, preferably: a story to make us feel the threat, rather than merely acknowledge it. And we have one. It’s the 1947 short story by John Cheever, called The Enormous Radio.

Jim and Irene Westcott are happily married, with two children. They live in a New York City apartment block, and they love listening to music.

One day, Jim surprises Irene with a brand-new radio. Irene is dismayed: it is massive, ugly, and far too expensive. Its dials are “flooded with a malevolent green light”, and it comes to life with a roar so thunderous that an ornament is knocked to the floor.

But there is something even more unsettling about this new radio. Irene discovers that it doesn’t just broadcast music. It broadcasts the voices of the neighbours, too.

Irene hears everything. She hears endearments, obscenities, sighs of despair. She hears conspiracies and lies. She hears a husband beating his wife – and Irene’s initial voyeuristic excitement quickly turns to dread. She becomes depressed, obsessively fixating on the inadequacies of her own marriage, and she is terrified to leave the radio on – perhaps because her neighbours can hear her, too.

The internet is the Enormous Radio. And we are the unwitting neighbours, spied upon in our most vulnerable moments.

But there are important differences. Though Irene can switch off the radio, the internet is always on. The radio can only spy on the adjacent apartments – but the internet is not so confined.

The internet has ears in our bags, in our cars, in the back pockets of our jeans. With the advent of wearables, the ears of the internet are on, and in, our very bodies. It’s not just in our homes that we are being watched, and eavesdropped upon. It’s everywhere.

Irene is the one listening in

If we are the neighbours, and the internet is the Enormous Radio, then Irene is the one listening in. Irene is every app, every social network, every website that we use. She is Facebook, she’s Dropbox, she’s Whisper. She’s Instagram and Twitter. She’s Google. She’s the government, as Snowden famously, or infamously, revealed.

But their knowledge doesn’t depress these internet Irenes. They don’t weep for us as our marriages break up, feeling our misery from a distance. Far from it. Our Irenes sit back, put ads for dating sites in our sidebars, and then watch for us to do something ill-advised in our grief. They rub their hands together as they wait for the cash – and the evidence – to roll in.

We argue and conspire - because we think nobody’s listening

At first pass, there seems to be a disanalogy. In Cheever’s story, the neighbours bicker, argue and conspire – but only because they think that nobody is listening. And we’re just not like that, one might object.

We are careful, in our online behaviour, because we are well aware that we’re being watched. We don’t just put any old thing on Facebook. We’re not that naive.

After all, we tell ourselves, the internet only tracks our public personas, not our private ones. We control what it sees. And what does it matter, if somebody sees these carefully assembled, artificial versions of ourselves? Who cares?

The thing is, the internet doesn’t just see what we want it to see. Its gaze is not limited to the airbrushed facades of our digital profiles. It peers around the corner, and it sees the tangled mess behind the scenes.

Think of all those outpourings of emotion that you’ve emailed to family, friends, lovers. Those are all on servers somewhere. Even if you trust your email provider, scandal after scandal teaches us that there are other enterprising third parties out there who might not be so scrupulous – folk with a knack for hacking and an eye on the bottom line.

Even the search engines know more than you think. Those inane questions you ask the internet, late at night, when you’ve had too much wine? They see those. That status that you almost posted last week, but didn’t, to your subsequent relief? They saw that. Those photos you thought you deleted, the ethnic or sexual biases you didn’t even know you had? They see those, too.

The internet is accountable to nobody

So far, for most of us, the radio has been on mute. It has kept its knowledge of us to itself. But what would happen if the dial were turned up?

Imagine the internet broadcasting your emails. Imagine it bellowing your search queries for everyone to hear. “Tim wants to know about cures for erectile dysfunction,” it might roar. “Jess is looking up abortion clinics.”

Make no mistake: our internet Irenes can speak. They have resonant, powerful voices, and at the moment, they are accountable to nobody. And if we don’t do something now – something to safeguard all of the information that they already control – they may well choose to use them.

Or, worse still, we might just give in. Our future online interactions might be stilted, guarded, fearful. We might be forced to show only our false, public personas to each other, so terrified are we to reveal our true selves.

Have we reached the peak of the privacy debate?

The digital privacy debate seems to have come to a climax. The release of Citizenfour, the new Snowden documentary, comes on the back of a steady stream of hacking scandals, trolling outrages, and heated debates about the “right to be forgotten” ruling.

Privacy concerns tend to follow mainstream technological advances, after a slight delay. And privacy was also at a tipping point when Cheever’s story was published. In 1947, when Cheever wrote the Enormous Radio, commercial radio entertainment was around 25 years old, and 82% of Americans were regular listeners.

What about today? Well, the web is 25 years old, and 84% of Americans are regular internet users. The rise of radio use had Cheever worried about privacy in 1947. And we should be worried now.

We have a choice

The unsettling tale of the Enormous Radio is at an end, but the story of the internet is not. And there is one more disanalogy to flag.

The radio was an inanimate object: an ugly, gumwood monstrosity, blinking at Irene with its ghoulish lights as it sat, hunched, in her living room. It relied on some occult power, rather than design, in order to spy.

But the internet is not magical, nor is it made of gumwood. The internet is not even an object.

The internet is just a big group of people, connected over protocols, sharing ideas. Since its inception, it has had a profound impact on the way we communicate. Like it or not, it will continue to shape our future.

As for the way we choose to communicate online in the future, however – we have a choice. We can continue to treat each other as mines of information to be bought and sold, as objects to be watched and censored. Or we can decide to treat each other as human beings. It’s up to us.