On top of everything else, the “bloody nose” would not convey the desired message, but would make North Korea cling to its nuclear weapons all the more. North Korea’s nuclear weapons program isn’t going to be “stopped” by an attack like this, so in addition to being illegal and insane it would also be ineffective.
The Insane Plan to Give North Korea a ‘Bloody Nose’
Furthermore, giving North Korea a “bloody nose” would probably be interpreted as a prelude to a full-on war for regime change. It would be impossible for the U.S. to credibly signal otherwise once it has already initiated an illegal and unprovoked attack. Once the U.S. initiates the conflict, North Korea has every incentive to cause as much damage as it can on the assumption that this could be their last opportunity. North Korea’s “bloody nose” would almost certainly mean the devastation of Seoul, it might lead to attacks on Japanese and U.S. targets, and it would probably cause a major crisis with China, and that’s one of the least disastrous scenarios.