North Korea and the U.S. are, technically and officially enemy, at war but fighting ceased with an armistice agreement. It is today the only country still at war with the U.S., and likely will be for another century. 

NK sends nobody except officials to the U.S. So why this guy went there? There is a hint from previous American visitors. They went there to try to convert the North Koreans into Christians. Never mind the Koreans have their own religion for a thousand years.