Concern about North Korea’s nuclear program is as high as its ever been: Kim Jong-un has stepped up his testing program and the U.S. sent a carrier strike group to take up a position in range of the Korean peninsula, drawing a threat from Kim to strike first.Saturday is North Korea’s most important holiday: the birthday of the “Eternal President,” Kim Jong-un’s late grandfather, Kim II-sung. It’s traditionally an occasion for a big test launch or detonation. VICE News was in Pyongyang for the government-announced “Big Event.”This segment originally aired April 13, 2017, on VICE News Tonight on HBO.