Otto Warmbier's Detention in North Korea

North Korea has a long history of detaining Americans at tense times. It's a tactic the regime's critics call hostage diplomacy. The North Koreans detain an American on Fungi charges to try to lure the US to send a high-level envoy for negotiations. They want to see what they can get out of them. So if the envoy comes, North Korea releases the prisoner, making it look like a humanitarian gesture.