Image copyright Getty Images

A section of the Berlin Wall on display in Seoul acts as a reminder of South Korea's fractured relationship with the North. But thoughts of reunification are never far away and there's a whole government department dedicated to the idea, although its staff don't seem very busy, writes Stephen Evans.

There is now a bit of the Berlin Wall in the middle of the South Korean capital. A concrete section of three slabs stands outside one of the museums as part of an exhibition comparing divided Korea with divided Germany.

Schoolchildren gaze attentively. They touch the rough concrete and take selfies in front of it. They are entranced by it - as they would be.

"If reunification could happen in Germany, why not in Korea?" is the question hanging over them and their country.

Under the South Korean constitution, the five provinces of North Korea remain part of the united Korea (which last existed 70 years ago) that South Korea continues to pretend to administer. I say pretend because in Seoul there is a whole building full of civil servants who technically oversee North Korea. There are departments for each of the provinces.

Except they can't administer them from Seoul because these provinces are in North Korea. There is the small matter of the inaptly named demilitarized zone in the way - Korea's version of the Berlin Wall.

I went to visit the ministry the other day and it has to be said that the Southern administrators of North Korea do not seem to be overburdened. There seemed to be a bit of online shopping occurring on some of the computer screens. And who can blame them? The imminent collapse of the North Korean regime has been predicted since 1990. And today it seems no nearer.

Image copyright Getty Images Image caption The demilitarized zone is an area of land about 250km (155 miles) long and 4km (2.5 miles) wide

The shadow government is in a gloomy building, with a staff of 44 people preparing for something not likely to happen soon and perhaps not ever. The corridors are long and empty and quiet.

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I met one of North Korea's putative rulers who told me that one of their main roles is to keep North Korean culture alive until the great day of reunification comes. That means organising folk-dancing displays in the South.

On their way into work, these theoretical administrators of North Korea pass a light blue postbox by the main entrance. On it is written in English: "Homesickness Post Box". This is for people from the North living in the South to post letters home - except that the letters will never get there because there is no postal service between the two Koreas. The postbox is a gesture, the administrator told me.

So is the ministry, if you ask me. There was a time, back in the 1950s and 60s, when the department was seen as a real government-in-exile, ready to take over. Nowadays, it is not. The bureaucrats there do not imagine that they will soon be sitting in similar seats in Pyongyang running the place instead of Kim Jong-un.

The talk in the South these days is not so much about the imminence of the collapse of the North, but more about the consequences whenever - if ever - it happens.

The exhibition in Seoul with the chunk of the Berlin Wall makes clear how different the Korean and the German situations are. There are charts showing how, even during the last years of divided Germany six million people were reunited with their families from the other side of the wall.

In Korea, in the past 14 years, the number has been less than 2,000. People in North Korea have virtually no contact with outsiders. All of East Germany, apart from the most eastern part around Dresden, could watch West German TV every night - they saw the outside world. North Koreans do not.

Image copyright Getty Images Image caption In October some families were reunited in North Korea

Incomes in South Korea are 10 to 20 times higher than they are in North Korea - a much bigger gap than that between East and West Germany. That means that if reunification happened, the economic jolt would be much, much greater.

Already, North Koreans who defect find that their skills aren't adequate for South Korea. Doctors who defect from the North often fail to pass standard South Korean medical exams.

This all indicates that the immense effort and money required for reunification would dwarf the scale of the task in Germany. But the bureaucrats in the shadow ministry in Seoul have some time yet to ponder the problem.

Kim Jong-un does not fear their imminent arrival to take his job in Pyongyang. In the meantime there is much to do - like a spot of online shopping and organising folk dances.

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