How will they do in a land, sea and air war if they can’t gas up their public?
That’s the “national security” question, and one neither North Korea nor the allies and South Korea are unaware of.
No doubt there is a certain level of reserves that the dictatorship thinks it needs whenever major hostilities were to break out, for any reason.
At some point the North may see THAT situation as a “now or never” situation, if even the military’s consumption is about to be consuming any national “mission critical” reserves.
If and when such a point is reached, look for Kim to try something crazy; and I would not even speculate exactly what that would be.