Chile’s Memory and Human Rights Museum is a big, green box that sits suspended above a sunken courtyard. Its crisp lines contrast sharply with the other public buildings in the Quinta Normal district, two metro stations west of downtown Santiago.

It’s a neighbourhood dominated by old churches, schools and an imposing national history museum. Dating back to the 19th century, these older buildings are decorated with tall steeples, bold columns and ornate cornices. Although they bear the scars of earthquakes past and graffiti present, they stand tall and resolute, refusing to betray their proud beginnings. They are grand buildings, built for grand purposes: glorifying God, marvelling at his creation and educating his creatures.

The Memory Museum is also bold but it is much more ambiguous. If it weren’t for the courtyard, the big, green box could easily be mistaken for a mail distribution centre. It’s also much more controversial. Opened last year, the museum tells the painful story of Chile’s military coup on 11 September, 1973, and the 17 year dictatorship that followed. Unlike the national history museum, which has three double wooden doors, its plain entrance is hidden from passers by, tucked away below street level.

I walk through the automatic glass door and approach the long desk where a bored woman is waiting. She tells me admission is free and although the small sign says donations are welcome, I only have a 10,000 peso note and that seems excessive. I ask for a guide book, which is also free, and then head up the stairs into the exhibition area.

The space is big and open, with lots of natural light. Not far from me, there’s is a big screen showing black and white footage of La Moneda, Chile’s presidential palace, under seige from its own airforce. In front of the screen is a man, sitting on a cushionless bench, watching. He turns and looks at me and our eyes meet. I look away, pretending to be interested in the sculpture behind me, and then I look back. He’s still looking at me. He gets up and walks towards me with an intense look on his face.

His head is bald and he is wearing a pair of tortoise shell glasses. Dressed in sneakers, jeans and a black jacket, he is quite short and he smells like shaving cream, hair clippings and chewing gum. It reminds me of the old-fashioned continental barber shop I used to visit when I was a schoolboy.

“Where are you from?” he asks. It’s clear that he’s interested in me because I’m a foreigner.

“I’m Australian,” I reply.

“I’m a Chilean,” he says, “and I lived through all of this. This is pure propaganda,” he says, gesturing over his shoulder at the screen which is now behind him. “It’s all lies.

“I was 10 years old all when it happened and I was only two blocks away from it,” he says, pointing at the screen again. “It’s terrible when an army has to attack its own government but this was necessary. Chile was in a terrible mess at the time. This place doesn’t tell you about that.

“If you wanted to buy bread, you had to wait in queues and people would start to fight with each other because there wasn’t enough bread. If you earned a dollar one day, it would only be worth half as much the next day. And then the next day, its value would halve again. The inflation was terrible.”

I don’t know what to say, so I just listen and nod. After a couple of minutes, he pauses.

“What’s your name?” he asks.

“Tim,” I reply.

“Jim?” he asks.

“No, Tim, with a ‘t’.”

“Ah, Tim. I’m Mario.”

“Nice to meet you.”

“Nice to meet you, too.”

Mario motions for me to come and sit  with him on the bench. Not knowing what else to do, I dutifully follow and we sit side by side, watching the screen. Bombs are falling on a building where I have stood taking holiday snaps, and tanks roll down the streets where I have stopped to buy refreshments. Mario keeps talking to me and I still don’t know how to respond, so I continue to nod. Above the screen, there is a timeline, explaining how the armed forces and police took control of the country in just 12 hours.

All of a sudden, Mario stops talking.

“Chau,” he says, before getting up and walking away. I continue to watch as La Moneda burns.

As soon as he’s gone, I kick myself for not talking to Mario more. I’m curious about why he was so keen to speak to me; why he approached an absolute stranger and presented his case, as if it were an absolutely normal thing to do. I wonder if he does it often.

I keep thinking about what he said. In one sense, he’s right. The museum provides no insight into Chile’s condition in the lead up to the coup. It’s as if it happened in a vaccum.

But it seems hard to agree that the coup was ‘necessary’, especially when I move across to a smaller screen and begin watching the sepia footage of the mass detentions. Uniformed officers frisk civillians and line them up against walls, ordering them to put their hands on their heads, as they point their rifles at them. According to the official inquiry, 2000 people were executed during the dictatorship and, almost 40 years later, 1000 remain ‘disappeared’ or missing. Unaccounted for. On one of the walls there is a massive display showing the portraits of these missing people. Most of them are smiling. Their black and white faces show no hint of the horror they would one day face. In another part of the museum there is a photo of their wives, or widows, marching in the streets and carrying posters posing a simple question: “Where are they?”

On another screen, the official explanation is summed up best by the head of the navy. Sitting alongside General Pinochet and the chiefs of the airforce and the police, in their first television appearance following the 1973 coup, he says: “After three years of supporting the cancer that was the Marxist Government of Salvador Allende, we feel obliged to act.” With those words, parliament was suspended and the rule of law was cast aside. Curfews were introduced and like the ‘disappeared’ victims, basic human rights left the scene.

I move across to a small table and pick up the headphones to listen to the last radio recording of President Allende, holed up in La Moneda. It is an odd mixture of resignation and indignation. The rhetoric flies from his tongue. He is lavish in his praise of the Chilean workers and scornful in his criticism of the “despicable” generals: “History will judge them,” he says.

“Long live Chile, long live the people, long live the workers…these are my last words…”

They are polemical and overwrought. But it’s hard not to be moved.

On the next floor I see Mario again. He is arguing with some young people who look like students. I walk past him and he doesn’t seem to notice me. Not far away is another screen with footage of the families of the ‘disappeared’, rallying together in the country’s National Stadium to seek answers. The woman watching it is crying. I doubt she thinks it was necessary.

Further along the same passageway, a pair of portraits grab my attention. They show the faces of two students, a boy and a girl, who were set on fire in the street in July 1986, not far from where I live. The boy died in hospital but the girl survived with second and third degree burns to 60 per cent of her body. I can’t remember what their crime was or who carried out the punishment. But that doesn’t seem to matter. This crazy event happened in the streets where I now walk, within my lifetime.

On the top floor of the museum there is a gift shop and an empty cafeteria with a balcony looking out over Santiago’s smog and skyscrapers. I don’t feel like eating anything but I do buy some postcards before leaving.

I’m ready to go and I hurry towards the Quinta Normal metro station. It seems appropriate to be heading underground, away from the city and its sad stories. Two stop later, I exit the train carriage and resurface. Stepping onto a bus, I switch on my MP3 player and a Chris Tomlin song comes on. I listen to the familiar words.

“You’re the God of this city
You’re the King of these people
You’re the Lord of this nation
You are

You’re the light in this darkness…”

When it finishes, I press repeat.