Should Washington take North Korea’s threat seriously? Washington and Pyongyang’s bluffs, posturing and brinkmanship in the run-up to the highly anticipated summit between President Trump and North Korean leader Kim Jong Un should be expected. Similarly, North Korea’s history of sudden diplomatic maneuvers — such as when it canceled a secretly planned meeting between US Vice President Mike Pence and Pyongyang officials during this year’s Winter Olympics at the last minute — is also well established. So Washington need not panic about whether the summit, which aims to end the standoff over North Korea’s nuclear weapons program, will indeed take place. But it also should not regard Pyongyang’s threat to walk away from the meeting as mere bluff. North Korea had called off a meeting with South Korea planned for Tuesday in protest over joint US-South Korean military exercises, which Pyongyang considered an aggressive gesture. Read more: Why the Iran nuclear deal’s collapse is a disaster for North Korea “I expected them to object. And perhaps, if the United States does not satisfy their demands, this summit meeting can be aborted,” Han Park told DW. Park is a former unofficial US-North Korean negotiator who secured the release of two detained American journalists…