san francisco dozen north korean economic officials visit california new york 2011 u.s. organizers hop tour would give delegation ideas market reform business innovations north koreans quickly make clear come want secure u.s. investment particularly restaurant giant yum brand inc yum.n say susan shirk university california san diego professor help organize visit really want get kfc north korea shirk say refer fry chicken chain add yum reciprocate interest recent years handful visit official delegations athletes provide rare opportunities ordinary americans north koreans come together exchange jeopardy president donald trump include north korea group nations face travel restrictions unite state share enough information visa applicants new policy come time heighten tensions unite state north korea pyongyang nuclear weapons ballistic missile test well escalate verbal threats country leader kim jong un travel restrictions unlikely broad impact number non-diplomatic travelers north korea per year rarely top 50 accord u.s. state department data human right activists worry sever one human bond isolate country west main point invite people give exposure u.s. see one open door bite say roberta cohen co-chair emeritus committee human right north korea state department official say restrictions necessary north korea cooperate unite state government respect fail satisfy information-sharing requirements visa applicants north koreans wish visit unite state must first obtain permission government apply visa person u.s. embassy typically beijing say robert king former u.s. special envoy north korea human right issue north koreans arrive unite state never go anywhere alone king say chaperon north korean government minders 2015 15 north korean weightlifters along coach reserve officials travel houston international weightlift federation world championships say phil andrews chief executive officer usa weightlift north korea plan early year take part 2017 world championships anaheim california november andrews say however know whether allow come new travel restrictions affect people already visa include waivers people certain tie unite state state department decline comment individual visa applications c. jerry nelson professor emeritus university missouri say visit serve humanitarian purpose 2011 four north korean scientists travel missouri collaborate u.s. counterparts soil quality test methods say order boost food production refer economic officials trip 2011 shirk say seem reluctant express opinions enjoy snapshot american life include visit mushroom farm department store new york carnegie deli arrange people go families dinner san diego say really like lot u.s. travel restrictions jeopardize rare exchange north koreans