The available data is spare:
- (38 North) Sohae Satellite Launch Facility: Activity at Test Stand, but No Evidence of Pre-Launch Preparations.
- DoD declines comment.
- Kim wants to make a big bang.
This is enough for speculation. What follows is compatible with the observations:
- Launch of an ICBM from a mobile launcher, but carried out at a prepared location, Sohae. This explains minimal activity at Sohae.
- The missile, mounted on a mobile launcher, is to be transported in an unfueled state. It will be fueled from the facilities at Sohae. This avoids the transport of dangerous chemicals over a primitive road system.
- The payload is a low yield nuke, probably just a naked boosted core. While a low altitude detonation avoids a large EMP event, it is not otherwise a requirement. An actual EMP attack requires a detonation in space. Hence a functional reentry vehicle, which has not been observed, is also not required.
- Although an exclusion zone will be announced, marine traffic immediately beneath the detonation will not be affected.
In the recent past, the North Korean nuclear program has exhibited jumps in capability without intermediate steps. Expertise and designs were bought. This scenario exhibits a jump, without the cost of actual development.
For propellant, North Korea uses UDMH; the oxidizer is nitrogen tetroxide. Although this propellant combination is storable in a fueled missile, transport accentuates the hazard, particularly over North Korea’s primitive road system. Dispersal of fuel supplies could be part of an operational strategy as well.
With noted small compromises, the prepositioning of fuel and limited yield, the intent is a visceral demonstration of EMP attack capability.
This is not a prediction. It is a hypothesis compatible with the lack of large scale resumption of North Korea’s nuclear program, with DoD “no comment”, and Kim’s desire for maximum shock value.