Almost half a century after the country was divided, the leader of the southern part made a historic journey north to meet his counterpart. "I shall get into terrible trouble for this," he told his host. "No," came the reply, "it is I who will get into trouble for this."
This exchange took place on January 14th, 1965, between the then Taoiseach Sean Lemass and Terence O'Neill, in the Stormont lavatory, so the story goes, and the Northern Ireland Prime Minister did indeed get into trouble as the North slipped into decades of turmoil and he found himself out of a job.
Yesterday, just over half a century after their country was partitioned, the leader of South Korea, President Kim Dae-jung, travelled north to meet for the first time with his counterpart, Mr Kim Jong-il, and no doubt both reflected on what sort of trouble lay ahead as they broke a historic logjam.
There are many parallels between Ireland and Korea, which is sometimes referred to as the Ireland of Asia. The two have a history of colonial occupation. The people of both Ireland and Korea also have an informality at odds with the more reserved social customs of the colonial power, which in Korea's case was Japan.
Prof Kevin O'Rourke of Kyung Hee University, one of the most highly acclaimed translators of Korean literature in the world, having completed 14 volumes of Korean poetry, recalls how he found the people of rural South Korea very similar to those of rural Ireland in humour and hospitality when he arrived in 1964 as a Columban Father. Recently a senior South Korean government minister related how much he identified with Frank McCourt's Angela's Ashes as it described the life of poverty in which he grew up.
The most obvious shared experience is that of partition. The border between North and South Korea is, however, much more formidable than between the two parts of Ireland, where Partition was never an impediment to free movement.
The frontier in Korea is a mined, barbed-wired no man's land, across which two heavily armed forces face each other. It is guaranteed by 37,000 US soldiers. The two Koreas are technically still at war since an armistice ended the 1950-53 Korean War. Millions of families have been separated and have not seen or heard from loved ones for 50 years.
Korea's misfortune was that it was an area of greater strategic importance than Ireland, and the border became a confrontation zone between two ideologies. The division had its origins in a decision by the United States during the second World War to encourage the Soviet Union to join in the war against Japan.
When Japan suddenly collapsed, Washington decided to carve up the Korean peninsula into two occupation zones. On August 11th, 1945, two American officers, Dean Rusk and Charles Bonesteel, were given 30 minutes to select an appropriate boundary line. They chose the 38th parallel.
After the 1950-53 Korean War, North Korea aligned itself with the Soviet Union and China, and the South became a protectorate of the United States.
The USSR collapsed and China embraced market economics. North Korea's leaders refused to abandon their communist system, and their country became an anachronism in the modern world. North Korea has all along underpinned its ideology with the ideal of self-reliance called Juche, which is "Ourselves Alone" . . . taken to its extreme.
The result is a country without computers, the Internet, mobile telephones, modern vehicles, up-to-date medicines or modern household devices. Its people are stifled by censorship and forced to live in a cultlike atmosphere of worship for the Dear Leader. Millions have died from hunger and related diseases as crops and farming methods failed in the 1990s. Its stunted children are centimetres shorter than half a century ago.
Contrast that with South Korea, the tiger of Asia, which has integrated with the global economy and, after a long struggle against military dictatorship, today enjoys democracy and freedom of expression. Where Pyongyang is a city of deserted avenues and power cuts, Seoul at night looks like a scene from the 1982 science fiction film Blade Runner, with giant television screens atop glass office towers.
Kim Jong-il now desperately needs aid from the south, the only entity prepared to devote huge resources to alleviating the north's poverty. The price he will have to pay is opening up to the world. Yesterday was the first instalment.
The experience of Germany shows that a homogeneous people divided by a Cold War frontier can reunite when ideology ceases to be a factor. Despite the pain and the affront to the dignity of many East Germans, who now can contemplate a divided Germany? The prospect of an eventual united Korea may therefore be more realistic than that of a truly united Ireland, as the divisions are not about long-lasting fundamental concepts such as nationality, sovereignty and religion.
Economists in Seoul say the south cannot achieve reunification by absorption, as did West Germany. But the first step towards reconciliation has been taken, and it is bound to have greater repercussions in North Korea than in the south. It is Juche which has failed.
In the circumstances, if the two Kims had a conversation like that between Lemass and O'Neill, it's likely it would have been the North Korean leader who would have said: "No, Kim Dae-jung, it is I who will get into trouble for this."