That said, since the announcement was made by some general, Kim can always pull back and not lose face.
Honestly, I have no idea.

North Korea does not have the technology to hit anything more than a few hundred miles away.  It's ICBM program is as worthless as a firecracker.  It does not have the capability of re-entering the atmosphere with a  bomb laden vehicle.  The whole thing just burns up on re-entry.

The threat to Guam and the west coast of the US  is still a couple years away at least.   So what Kim means is that a whole bunch of really small burnt up missile parts might  get close to Guam, but isn't going to cause any damage.  What Kim is really doing is repeating what the rest of the world knows.  Trump is a blowhard moronic fool with no understanding of any real issue facing the Korean Peninsula.