“What motive do the Norks have to kill him.”
They didn’t want to kill him, but rather they wanted to abuse him and they wanted to see just how far they can abuse an American citizen (and it was a given Trump would find out about the abuse and they wanted to test him).
Things went too far and oops, $h!t happens. Probably testing new interrogation methods and technology as dictators are inclined to do (recall the torture and medical abuse by the chinese and norks during the Korean War).
Remember, to a society that is convinced Americans and others are sub-human, torture and other abuses are allowed and encouraged.
My guess. . .
Perhaps we should send the BLM over to NK so they could confiscate some cattle