Mauerpark is home to some of the few remaining slabs of the Berlin Wall. They are dotted neatly along Bernauer Straße and flanked by a visitors’ centre and tower. Tourists climb the tower and look down on the street, imagining it divided in two.

A few weeks ago, a Mercedes pulled up on Bernauer Straße. Michelle Obama and her daughters got out. They were met by a man in a black suit. As they made their way into the visitors’ centre, he gestured to the area around them and they nodded attentively. A few minutes later, I saw their tiny heads at the top of the tower.

Lately I’ve been spending my evenings on the other side of the park, closer to the stalls housing ponies and goats and pens full of guinea pigs. I go there after work and read Stasiland. It’s a paperback with a yellow and black cover. The ‘L’ of the title has been extended to separate Stasi from and. I avoided it for months, admiring instead the bold colours of its spine, which stood out like a bee among the other titles on my shelf. I had got it into my head that it would be a bleak read; more of a history lesson and less of a story.

I was wrong. It is compelling and original. The author, Anna Funder, tells remarkable stories in unsentimental language. She is a master of observation – a fitting tribute to her task, which is unravelling the lives of East Germans constantly under surveillance.

I don’t just go to Mauerpark to read though. I go to watch.

There are two places I like to sit.

The first is on the top of a hill covered in purple flowers that look like lavender but which somebody told me, categorically, they are not.

The second is in an arena made of concrete. On Sundays, an Irishman with a battery-powered box moderates enormously popular karaoke sessions there. During the week though it is populated by shaggy-haired men playing guitar, groups of teenagers with shisha pipes and old stooped figures moving quickly up and down, collecting the glass bottles people discard on the ground. Later, they recycle them for cash.

Once I observed three teenagers in an unequal relationship. They were sitting in the centre of the arena. The two girls would kiss and hold hands while the boy sat beside them drinking beer. Then one of the girls would break off from the other to wrap her arms around the boy and climb onto his knee, while the other sat alone. The relationship seemed to intersect around one of the girls; the other two didn’t touch. After some time, the girls took each other’s hands and walked away, leaving the boy – and me- watching them from behind.

I also watch people setting up picnics, cooing at their babies and shooting basketball hoops.

It doesn’t occur to me that I am being watched.

The office where I freelance is close to Mauerpark. My job requires me to write about German news, in English, very fast. In the past few weeks, one face has been appearing on top of several of my stories.

It is young, chiselled and bespectacled.

It’s Edward Snowden. There is a stock photograph that the agencies have which is a still from an interview that was recorded last month.

I’ve looked at it carefully. Snowden is facing the camera at an angle. His image is reflected in the mirror behind him and his expression is tense but firm.

When I write about him I use terms like “NSA whistleblower” and “fugitive” because that’s what everybody else is calling him.

I dutifully record the sequence of events as they appear in the agency feeds and try to come up with snappy headlines to fit the stories.

But the more I see Snowden, the more uncertain I become.

When it broke that US intelligence agencies were monitoring vast amounts of telecommunications, I was surprised it was a story.

Wasn’t it a given?

I wasn’t alone in my reaction. Others have told me, somewhat sheepishly, that they too expected it to be the case.

News of microphones in EU offices did shock me though. Unlike the internet, they are tangible devices. People need to conspire to plant them. They feature in detective novels and in the Cold War.

And as sometimes happens, I began to question myself.

‘Virtual reality,’ I thought, is an oxymoron. Spying on the internet requires forethought too.

And taking the technology for granted only adds to its sophistication.

Most of the time I am content to be gratefully bamboozled by how it is that the face of my friend in South Sudan can pop up on my screen or that my boyfriend and I can share a beer together – he in Edinburgh and I in Berlin.

But reading Stasiland and writing about Edward Snowden has caused me to uncover an uncomfortable truth of my own.

I have underestimated the capabilities of those in power. And I have become inert, thanks to a life full of comfort.

I escaped World War II by just fifty years and was four when the Cold War sort of ended.

But I figured – out of laziness – that nobody could be watching me and that those that are being spied on, probably deserve to be.

I have, it seems, a trust in authority that has only just become explicit.

Edward Snowden, a disillusioned geek, is just five years older than me. I am impressed by the hysteria he has unleashed. It, rather than anything he’s revealed, has shaken me up.

I’ve learnt that I live in a world where a plane carrying Latin American dignitaries can be forced to ground on the suspicion that a tech-clever ex-contractor could be on board. I’ve learnt that the balance of power in the West is an uncomfortable thing. And I’ve learnt something I keep learning: that I know very little about anything at all.

Yesterday, my colleague and I took our lunch to Mauerpark. She had bought a punnet of raspberries and we were munching them in the sun. A man with sun-tanned skin was loitering close by, watching us. After a while he lay down on the grass and curled up with his back to us.

Then suddenly we felt him looming. He asked, in Spanish, for a raspberry. When we gave him one, he disappeared.

Minutes later, a man in sunglasses, shorts and a baseball cap raced towards us.

“Was that guy just now hassling you?” he asked. He sounded panicked.

“No” He just wanted a raspberry,” my colleague said.

“Have you got everything?” the man said. “Quick, check for phones and money!”

We rummaged through our bags. Everything seemed to be intact.

“You sure?” the man asked. He was rushing onto the road.

“Wait,” we called after him. “Is everything okay?”

“Yeah,” he said, without stopping. “I’m a cop.”