Ahead of Thursday's 70th anniversary of the start of the Korean War, Pyongyang through the ruling Workers Party newspaper Rodong Sinmun has warned that last week's blowing-up north of the demilitarized zone of the Pyongyang-Seoul liaison office was "just the beginning". Why now? Will John Bolton’s criticism of South Korea's president pour fuel on the fire? Is it all over for the diplomacy that three times brought together the leaders of North Korea and the United States? Or is this Pyongyang's way of seeking attention at a time when further progress has stalled?