Again, there is nothing to stop celebrities doing their military service before they start performing but, even were that not the case, military service is not something that is undertaken because it is convenient or easy but rather something that is done because it is necessary. The country is at risk of invasion, it is still technically at war with the North and in the last Kim Jong-Il has become increasingly erratic.  Of all professions surely performers, with their peculiar interest in the combination of a consumer society and the right to freedom of expression have the greatest interest in insuring that the north doesn’t invade. Neither wars nor dictatorships are particularly known for encouraging the performing arts.