2016APR26 [연합뉴스(영문)] Former U.S. official says U.S. does not rule out first-use nuclear option against N.K. zoom + zoom - print social share Facebook Twitter social share Facebook Twitter [연합뉴스(영문)] 2016-04-26 Former U.S. official says U.S. does not rule out first-use nuclear option against N.K.