One of the biggest stories of the year has been the perhaps-not-shocking revelation that the American NSA and our own GCHQ have been snooping on our everyday communications. Becky Hogge writes about how we're struggling to grasp the consequences of this erosion of our rights, and asks what we might do to counter it

In October 2003, AT&T technician Mark Klein was transferred to a new post in the company's San Francisco office on Folsom Street. Soon after he arrived, he became aware of a room – Room 641a – to which only technicians with clearance from the National Security Agency were permitted access.

After his retirement in 2004, Klein blew the whistle. He backed his claims – that AT&T were illegally tapping the phone calls of every American they could, in a scheme he labelled "Orwellian" – with internal company design documents. Digital freedom fighters the Electronic Frontier Foundation (EFF) used those documents to sue the US government, in a case that for ten years tried to prise open the door to Room 641a.

This year, NSA contractor Edward Snowden smashed that door down. And like the door to Doctor Who's Tardis, what lies behind it goes on and on. Since midsummer, the steady stream of disclosures served by Snowden's leaks mean we now know several things we once could barely imagine.

The NSA can fast-track requests for access to details of all our private communications and other online activities from most major US internet companies. When it can't be bothered with that, it can hack some of those companies' internal networks direct. Somewhere on a beach in Cornwall, GCHQ, the NSA's UK counterpart, siphons off data from the trans-Atlantic undersea cable that carries a significant percentage of the world's internet traffic. And GCHQ and the NSA have been working together to undermine the encryption technology that secures the entire trillion dollar global e-commerce industry.

So it turns out that the internet is just one big machine for states to spy on their citizens. For many reasons, we should not be surprised. The war on terror has created a political environment in which we are forced to accept the existence of an enemy within, acceptance that in turn justifies levels of state aggression against citizens once only reserved for other states.

Technical conditions, too, were ripe for this. Data is to the information age what pollution was to the industrial. How could the spooks be expected to resist knowing the loves, lives and locations of a million potential terror suspects?

And the business conditions were also favourable, because the major companies complicit in the NSA and GCHQ's shenanigans – Google, Facebook, Yahoo! et al – happened to share a business model with the spooks. It wasn't hard for these guys to get the NSA all the data, because getting all the data was what they were in the business of doing.

For all these reasons, then, we should not be surprised. Yet for many other reasons we were. The internet was sold to us as a tool of liberation. It felt free. Not just because, after one monthly payment, almost everything on it was free of charge, from email and social networking to a musical back catalogue or three. We felt freer using it: freer to express ourselves, to find out about our world and to try and change it for the better, whether that meant signing a few more petitions than we might have done had we had to lift up a pen, or taking to the streets to sack our government.

For picture editors, it's been a tough six months. The door to Room 641a is just a door, but it may be one of the most pictured doors in news history. It forms the front cover of Mark Klein's autobiography Wiring Up The Big Brother Machine... And Fighting It. Wired magazine even have a slideshow of it, pictured from two angles. Similarly, after they got bored of running shots of the beautifully non-descript Snowden (no white-headed Julian Assange he), the picture desks at the newspapers brave enough to run his stories stuck with images of the doughnut-shaped GCHQ building in Gloucestershire, and the NSA's mirrored box headquarters at Fort Meade.

This is important, because it indicates something deeper at play. Simply put, it means we – collectively, all of us, not just the Guardian's visual editors – cannot picture what the state of affairs as has now been revealed to us means. We don't understand it. If this were a murder mystery, we'd be at the start, with nothing but the yellow-tape outline of a dead body to go by. We know where the crimes took place, but we don't yet know why, or how to stop the killer from striking again.

What, then, does the world look like once we get through the door, inside the building? What are the contours of this new age of total electronic disclosure?

It's not only about Facebook, by which I mean it's not only about the minute details of your personal life being available to any petty bureaucrat with a grudge. Although for a few people, it will be all about this. The price of dissidence, including that of a President standing up to the war-mongering national security lobby within his own administration, rises as privacy erodes.

But for the majority, it's not Big Brother that is the threat here, but Big Data. One of the other ways picture editors like to illustrate stories about surveillance – and stories about technology in general, really – is with walls of green ones and zeros, rushing across vast screens. In the NSA's world, we are those ones and zeros. They are the people we talk to, the places we've been and the things we've bought. But they are not these things as they are – rather, they have been isolated from the rest of our lives, scrubbed up, and magnified. They have been matched against patterns of behaviour of people we've probably never met. Welcome to governance by algorithm.

As Evgeny Morozov has pointed out, the addiction to data – call it dataholism – evinced by the security services is just a very well resourced and efficiently run version of a phenomenon happening in all parts of our modern life. Our access to credit, our likelihood of being audited by the tax man – even our ability to get on a plane and get the hell out of here – are already to a large extent mediated by computer.

Where once human judgement and moral code led our reasoning, soon proprietary algorithms run on vast data troves will decide our fate. Correlation will replace causation. In this world, arguing your case against what the data says you did or thought becomes hard if not impossible. Conformity to someone else's model of how you should live becomes the easiest option.

This future is not inevitable, at least not yet. Indeed, Snowden's revelations could still become a turning point, the moment we pulled back, rethought, and changed course. Those already calling for change have some powerful allies, from the US technology companies fearful of the risk openly conspiring with the NSA poses to their business, to world leaders like Angela Merkel of Germany and Dilma Rousseff of Brazil pushing back against US surveillance on the international stage.

But for this movement to succeed it needs ordinary people – law-abiding, Facebook-using, iPad-buying citizens like you and me – to be a part of it. It needs us to take the time to imagine what's going on in the buildings we've seen dominate our newspapers since summer, and work out whether we like it and the future it portends. And if we don't, then we can join organisations like the EFF and its UK equivalent, the Open Rights Group, in opposing it.

So go on, make 2014 the year you put yourself in the picture.