the united states. the question seemingly prompted by a report in a south korean newspaper saying kim had invited trump to come to pyongyang. cnn has not independently verified the report. trump has said he would invite kim to washington during an impromptu meeting at the dmz. i would invite him right now to come to the white house. reporter: but a sitting american president traveling to the secretive, hermetic north korean capital would be unprecedented. a truly historic moment. still, some veteran diplomats agree with the president, that it s a bad idea right now. kim would consider this a greet victory, a great coup to have donald trump in pyongyang. the president should not do it. the president appears interested in these kind of summits that give him a lot of publicity, but they undercut his authority and his credibility. they make the united states, frankly, look weak on the global stage. reporter: jimmy carter and bill clinton have traveled to north korea to secure the