Even assassination is unlikely to help- Kim would just be replaced by the most ruthless of his Generals, and we might be be in a worse position (if possible) than we are now.
Americans do not have a great record for seeing big wars coming- in fact, I think we have never anticipated the outbreak of a major war. We want to be happy and carefree, and even now at least half of the population doesn't believe that there really are evil people in the world.
The article is correct, though, that if China decided to lean on North Korea, a very destructive war could be averted. Will they?