Back in the day, the original evil Kim only would saber rattle during the big exercises like Team Spirit and Foal Eagle. UFL in August? He didn’t waste any saber rattling on it.Turns out the exercise crazy little fat boy is so concerned about, Dong Maeng 19-2, is a Command Post exercise...no movement of troops, no field exercises. Their reaction to it, "It is crystal clear that it is an actual drill and a rehearsal of war aimed at militarily occupying our Republic by surprise attack and rapid dispatch of large-scale reinforcements,"
The threats would be amusing if you couldn't tell you were talking with crazy people. Typical to their negotiating style they want to get something for nothing. The talks were about denuclearization of the crazy nuke happy Norks, the Norks keep trying to turn it into unilateral South Korean disarmament. The Norks will only feel secure in their insanity when they are no longer constrained by US and SK forces. The Norks never stop planning for war; SK has no choice but to reciprocate (well, there are bad choices...the kind Moon has made in the past).
In all likelihood they already have some new weapons that needed testing and were looking for any excuse.