North Korea is threatening to pull out of the Korean War armistice.
It seems like they're trying to esclalate this thing just when the U.S. is about to get involved in Iraq. I don't know if they'd be bold enough to attack the South, even with the U.S. otherwise occupied, but they may keep pushing for things like this, just because no one can stop them right now.
If they still think like this, I don't know if it's realistic to expect the south's "Sunshine Policy" to work...