Kim Jong Il's death leaves the Korean peninsula and the rest of East Asia in a period of great uncertainty. But one of Kim Jong Il's most dangerous legacies has security implications well beyond the region: he leaves behind a thriving nuclear weapons export business that must now be stopped.
There has been mounting evidence in recent years that North Korea has set up an illicit nuclear export business to Syria, Iran and potentially elsewhere. Syria's Al-Kibar nuclear reactor, which was bombed by Israeli warplanes in 2007, closely resembled a North Korean facility used to produce plutonium for bombs, and one western diplomat told me that several senior North Korean technicians were killed in the raid. (See photos of Syria's nuclear reactor destroyed in 2007.)
North Korea and Iran's sharing of technology for missiles that could be used to deliver nuclear warheads is so extensive that some analysts say it is only appropriate to view it as operationally a joint missile program. No one knows if North Korea is also helping Iran with nuclear weapons design, and it's possible it has other, yet-to-be-detected clients as well.
North Korea shares little similarity or ideology with Syria or Iran; its dealings are largely profit-driven. For its clients, DPRK provides a black market to purchase sensitive nuclear technology without detection by the international community. The nightmare scenario is that Pyongyang would even sell fissile material -- the key ingredient for nuclear bombs -- to terrorists if the price is right.