As politicians and analysts argue about the health of Kim Jong Il and his totalitarian regime in North Korea, Woo Kee-sup is troubled by a more basic concern -- if the North were to fall, how many of its 24 million residents would be ready to live in a modern society?
Running a small private school that works with North Korean defectors in their teens and 20s, Woo has a firsthand look at students produced by the educational system in the Hermit Kingdom, and the news isn't good, he says.
"Some of them have graduated from high school in North Korea, but their learning capacity is very poor," said Woo, a 64-year-old retired technology executive. "In some cases, we start out teaching them at the elementary school level."
Although the Yeomyung School that Woo heads near central Seoul offers just a snapshot of the issue, it's a worrying reminder for South Korean leadership that should the North collapse, millions of undereducated, traumatized and malnourished North Koreans might come flooding across the border.
"Everybody has the same reason for leaving (North Korea): They're hungry," said a 28-year-old student at Yeomyung School, a woman with bangs in her eyes who like many of her classmates looks small for her age, a calling card of years of poor nutrition. "It's just a question of how long they suffer."
The woman asked that her name not be used for fear of bringing retribution, as in labor camps or worse, to relatives still living in the North.
Kim and his father before him have ruled North Korea for more than 60 years with a cult of personality that's combined ruthless state power, poverty and near-total isolation from the outside world. The result by all accounts is a nation of people who would be startled, if not stunned, by the bright lights and hustle of Seoul, and might in turn overwhelm South Korea's ability to absorb them.
Woo said that his 65 students face difficulties with broad issues such as political freedom, but also the dizzying details of their new lives -- roads full of traffic, ATMs, nightclubs and big department stores.
In the last three years alone, the number of North Korean defectors in the South has doubled from 10,000 in 2007 to more than 20,000 this year, according to the South Korean government.
When those numbers were announced last month, South Korea's minister for unification, Hyun In-taek, visited Yeomyung to reaffirm the South's commitment to looking after those who'd escaped the North.
Asked recently what would happen if it were millions, and not thousands, of North Koreans coming south, Woo shook his head and said, "There would be a lot of chaos."
While predictions that Pyongyang will crumble are as frequent as they are wrong, concerns have been magnified this year by an increase of aggressive behavior by the North -- the torpedoing of a South Korean warship in March that killed 46 sailors and an artillery barrage on a South Korean island last month that killed four people.
Many observers link those attacks to questions in Pyongyang about whether Kim's heir apparent, a son only in his late 20s, would face being overthrown by older relatives or military commanders after his father dies. Kim's health is suspected to be on the decline after a 2008 stroke.
South Korean President Lee Myung-bak earlier this month added to the growing sense that change will come sooner than later, saying, "I feel that reunification is drawing near."
A study commissioned by the South Korean parliament projected the costs of reunification at some $1.3 trillion, according to the Yonhap news service in Seoul. There have been suggestions that should Pyongyang collapse, the figure could be higher.
"I don't think there's any shortcut, it will take all of the efforts we can put forth. This is something we will bear on our shoulders," Kim Jeong-ro, an official at South Korea's Ministry of Unification, told McClatchy Newspapers.