precedent for that. in fact, almost ten years ago exactly this month, june of 2008, north korea invited cnn, a u.s. diplomatic envoy to witness the demolition of a water cooling tower in another facility that was used for plutonium enrichment. this wblew the tower up at a point of negotiations over its nuclear weapons program. and unfortunately, the negotiations deteriorated. and within a year of that ceremony, north korea conducted another nuclear test. george? >> ivan, so is north korea making gestures of good will ahead of the summit? we're getting to see what they plan to offer. but now we're also seeing what the united states may offer in return. tell us more what you're hearing. >> yeah, that's one of the big