"Indeed, Kim Jong-il or whoever succeeds him will inevitably destroy South Korea's economy and her people. However, the technological leaps they'll make by milking every red penny out of the South Korean economy, along with the revitalization of their military, will make them a direct military threat to Japan, and a potential nuclear threat to everyone in the world."
They are already nuclear capable. The CIA issued a report in 1994 that they "most likely possess at least 4 atom bombs". Atom bombs are smaller then thermonuclear fission, true, but think of a repeat Hiroshima. The North now has the missle technology they need. Nukes and missles, what other real technology does a country need to destroy it's enemies?