Over the past five years, North Korea has constructed several military facilities on small islands surrounding the city of Sohae, a leading missile development and testing site. In some cases, the islands themselves were constructed; what amounted to little more than a pile of sand 20 years ago is a burgeoning military facility today. Sohae, a sizeable metropolis on the country’s west coast, has hosted many critical missile tests, including the 2012 and 2016 Kwangmyŏngsŏng satellite launches. It is the prime research and development hub for key intercontinental ballistic missile (ICBM) technology. Sohae is expected to host more missile tests in the coming years as North Korea focuses its efforts on ICBM development.
North Korea has built at least five military facilities on islands near Sohae. The islands identified in the infographics below are not uniform in size or geological structure, and their military facilities are not identical to one another. Their missions may likewise be individually distinct. Some of the new facilities may not even be primarily served by Sohae’s military facilities, but by other nearby bases. We have dubbed them the “Sohae islands” because Sohae is the most significant political-military structure nearby.
The mission of these new island bases is not obvious. Available geospatial intelligence doesn’t align neatly with a basic strategic analysis. Some of the islands look like offensive asset deployment sites — that is, ballistic missile launch pads — but building Transporter Erector Launcher pads on these islands would not be strategically wise. Anti-air missile sites would be a strategically wiser choice, but the available imagery lacks some of the evidence traditionally indicative of such deployments. Missile silos are a distinct plausibility, and one that would make a fair amount of sense. However, it is exceedingly difficult to ascertain the structure, size, and nature of these islands from the available imagery. Whether they could structurally support a missile silo is unclear.
TELs, SAMs, and Other Assorted Acronyms
As Sohae’s target value rises, that the North Korean military may be dispersing its assets into nearby facilities. Firing exclusively from Sohae’s resident Tongch’ang-ri Launch Facility during wartime would be a dangerously predictable, amateurish mistake. But constructing island launch sites would buck the common and cost-effective practice of building remote TEL pads hidden between mountains. If North Korea intends to use these islands as offensive sites, then it has found an awfully expensive way to reap only marginal strategic benefits.
Turn your attention to the paved, rectangular lots shown on Islands A, C, and E in the above image. These empty lots could plausibly accommodate a North Korean ballistic missile and the Transporter Erector Launcher (TEL) it rode in on. These TELs — those vehicles so frequently touted in North Korean military parades, ballistic missiles stacked neatly on top — could disperse from their shelters and onto these various islands during times of heightened tension.
Though most of the islands in the attached infographic resemble facilities designed to host missile launchers, the evidence is not definitive. The wide roads leading on and off the pads at Islands A and C could allow for rapid shooting-and-scooting. But Island E’s single road looks rather inconvenient for a wheeled TEL. (Notably, some newer North Korean missiles such as the Pukguksong-2 use tracked, rather than wheeled, Transporter Erector Launchers.) Additionally, the nearby military structures on these islands do not appear to be protected by a blast shield of any sort, and swaths of heat-resistant cement are not always visible. However, the latest available imagery is from December 2016; these construction projects could have been completed in the intervening time. The geospatial evidence is decidedly mixed. If the islands are intended to eventually host ballistic missiles, then North Korea made an oddly poor decision.
North Korea is no stranger to target dispersal, a fairly basic strategic principle. The DPRK knows that during a war, firing exclusively from well-known sites like Sohae’s resident Tongch’ang-ri Launch Facility would be a dangerous mistake. Accordingly, most North Korean TEL pads are tucked between remote mountains and stuffed behind far-off hills. By building a multitude of TEL launch sites and dispersing them widely, North Korea has made it nearly impossible for any adversary to neutralize its ballistic missile arsenal in a first strike. If the United States and its allies launched a full-scale assault on all known North Korean military targets and somehow managed to strike all targets nearly simultaneously except one, the consequences could be thoroughly devastating. Just one lonely TEL, hiding deep in the mountains — or on an island near Sohae — could launch a nuclear-tipped Nodong missile at Seoul or Tokyo and instantly cripple a U.S. ally. It is this concern that kept the Kim regime alive during the Obama administration.
Building TEL pads on previously uninhabited islands would be more expensive and less secure than constructing an equal number in nearby mountains and valleys. As North Korean air defenses are paltry at best, the DPRK’s second-strike capability is preserved almost exclusively by the secrecy shrouding their missile storage and launch sites. In contrast, the Sohae islands are quite exposed. If North Korea’s recent rash of island-building was an attempt at mere target dispersal, then they chose perhaps the least cost-effective method possible.
Though critical ICBM technology is tested at Sohae, it — like many of North Korea’s important research bases — lacks adequate air defenses. (Indeed, the whole country does.) The DPRK has few surface-to-air missile (SAM) systems, and necessity demands it defend its airbase with old planes and even older guns. These defenses are nominal — the majority of 4th and 5th generation aircraft can easily destroy or avoid them. Sohae is protected more by its proximity to North Korean air bases than by point defense systems deployed at the base itself. That may change soon.
The square-ish, paved concrete pads on Islands A, C, and E may not be intended to host ballistic missiles like the Nodong or Musudan at all. SAM batteries could be reasonably accommodated on any of those three islands, in some cases pending minor-to-moderate construction projects that could have been completed since the satellite photograph was taken. North Korea is still testing its new KN-06 air defense system, a reasonably modern design roughly on par with the Russian S-300. When North Korea eventually introduces the KN-06, Sohae may host a few of its own, perhaps on Islands A, C, or E.
As with other proposals discussed here, the evidence for a SAM deployment is mixed and the picture incomplete. Surface-to-air missile deployments would require supportive equipment like radars, infrastructure improvements such as bulkier revetments, and command posts. We have not seen evidence of these on the Sohae islands. Plans for those could be underway; stationing SAMs on some of the islands would not be a bad idea. Or it could be that the DPRK intends something else entirely.
An offensive ballistic missile deployment makes little sense, and the available pictures are missing some of the infrastructure indicative of one. An air defense deployment makes more sense, but there still isn’t enough evidence to support the presence of necessary infrastructure. A third option, that some of the structures pictured are missile silos, would make some logistical and strategic sense, and the surface-level infrastructure does look quite similar. Compare the diagram below of a missile silo to some of the Sohae islands (particularly B and C). A superficial resemblance, undoubtedly. However, it remains unclear whether any of the islands could structurally support an underground silo. Remember, some of these islands were just sand a few years ago. These pop-up facilities could also potentially be dummies designed to misdirect an adversary’s tacticians.
There is not enough open-source information to confidently determine the mission of these new island structures. Their purpose remains elusive.
The “Sohae islands” may sprout new buildings or host missile tests. The KN-06 air defense system may arrive — on the islands or elsewhere — to defend the city’s critical military infrastructure (and the lives of its inhabitants). Without question, key ICBM components will continue to be tested at Sohae, whether from an island or the Tongch’ang-ri Launch Facility on the mainland. The city is rising in strategic importance as North Korea focuses more and more of its efforts on mastering ICBM technology. In fact, if North Korea follows through on its recent pseudo-threat to test a new missile every week, all eyes will be turning to Sohae very soon.