South Korean leaders are afraid that the leadership in North Korea is losing it. The newly revealed secret nuclear weapons program up there, in violation of the 1994 treaty, was bad enough. But when that program was discovered (largely because a North Korean defector pointed it out for US spy satellites), North Korea basically said, "so what?" To the northerners, their secret program was based on a different technology (enriched uranium gas diffusion, apparently bought from Pakistan) that was not covered by the agreement.  The 1994 treaty was very generous for the north. In addition to six million of tons of fuel oil delivered annually, South Korea and Japan were building two 1,000 megawatt nuclear power plants in the north. These were replacing the five megawatt reactor (which generates plutonium) that North Korea is restarting, and a 200 megawatt plant that was under construction (work was halted). Both of the North Korean plants were designed to produce nuclear weapons plant, the two 1,000 megawatt plants do not. The northerners, as was their custom, were delaying work on the 1,000 megawatt plants. For the last half century, the north has consistently negotiated using an irritating stop and go, rant and rave, style. Making outrageous claims and demands has often worked for the north, so they don't see their negotiating style as counterproductive. But the leadership up there has been running a brutal, economically inept police state for the last 55 years, so they can believe anything they want and feel they can get away with it. Until now. The country is starving, and the 1994 deal provided fuel, food and other aid that made the difference between life and death for many North Koreans. Now the North Koreans are trying to keep their nuclear weapons program and still get the life saving foreign aid. But the rest of the world isn't cooperating. The only threat North Korea can make is an invasion of South Korea.  This would cause a lot of damage, but would result in the destruction of the North Korean dictatorship. Nuclear weapons are another matter. The threat of nuclear warheads on North Korean missiles improves the North's ability to extort money from South Korea and Japan. But South Korea and Japan are getting tired of the extortion game, and agreed, with the US, to cut off the monthly oil shipments when the North's illegal nuclear bomb program was discovered. What no one knows for sure is whether the North will again do what it did in 1950; believe it's own threats and propaganda and invade the south.