home after pyongyang closed access to an industrial park. on tuesday, john kerry announced he will travel to seoul after kim jong un's latest power play. we have the report. >> reporter: kim jong un undid years of diplomacy. the reactor capable of producing enough plutonium to make a nuclear bomb a year. they closed it in 2007, destroying a cooling tower to show its commitment to a now shattered deal with the u.s. >> if they restart their nuclear facility, that is a direct violation of their international obligations and would be a very serious step. >> reporter: kim i don't think unshows no sign he's listening to the outside world. it would be a mistake to dismiss