The most interesting, and certainly the most chilling, experience I had in four days in Buenos Aires was to visit the memorial to “the disappeared.”

Two of us were taken there by a doctor whose brother and sister in law were both among the disappeared. He and his wife brought up the two small children who were left.

Some 30 000 people disappeared between the early 70s and the early 80s. The military government snatched them, tortured them, often to death, and then dropped their bodies from planes way out in the Atlantic. Sometimes they drugged the disappeared heavily and dropped them into the water still alive.

They were called the disappeared because no bodies were found and because when the general heading the government was asked what had happened to these people, had they been murdered, he answered that they “just disappeared.”

My friend’s brother knew that he was in danger. His family urged him to flee, and many people – mainly young intellectuals – did flee. But his brother refused. He loved his country too much. My friend is proud of him and it’s some comfort to him that he knows that he wasn’t tortured to death. When they snatched him he ran, and they shot him. He was 27.

The sister in law of my friend was younger, and she was tortured to death. By a fluke she managed to ensure that her young children were not taken. Usually children were taken and given to new families.

My friend then left the country with several young children. Many of those who fled never returned.

The memorial is by the Rio de la Plata, the world’s widest river. When we were there it was cold, grey, and windy, and nobody else was there. There are sculptures that create the impression of a graveyard, an empty graveyard, but the main feature is two long, grey slate walls that list the names of the disappeared by year. Name after name after name. My friend’s brother was taken in 1976, the year that the most people were taken – and the year I graduated from medical school. His sister in law was taken in 1977. When we reached her name, my friend touched it gently.

Nobody has been tried for these crimes. The perpetrators were given an amnesty. There has been no justice, but the present government may charge people.

The mothers and grandmother of the disappeared keep the memories alive. Every Thursday afternoon they walk in a circle in the large square that contains the pink presidential palace, where Eva Peron appeared on the balcony to huge adoring crowds.

I then flew onto Lima and met another friend who told me of the 70 000 who have disappeared in Peru, mostly not well connected, middle class intellectuals but poor indigenous people.

We must not forget.