What to make of North Korean naval modernization?

The views expressed here are the author’s alone and do not represent the official position of the Navy, the US Department of Defense or the US government.

Introduction

Over the past two decades, assessments of Korean People’s Army Navy (KPAN) have been largely pessimistic. The surface fleet, though large in numbers, is composed of small patrol vessels and largely confined to coastal operations. Most of these ships have weapons systems and sensors that are outdated and no match for the Republic of Korea (ROK) and US Navies. The appraisal of North Korea’s submarine fleet is only slightly more positive. With 71 boats, North Korea has one of the largest submarine forces in the world, but these too are old Soviet-era models or midget submarines that are unable to venture far from coastal waters. The noteworthy exception in the submarine force are the one or two boats intended as launch platforms for nuclear-tipped ballistic and cruise missiles. However, these submarines are also loud and easy to track. Over the years, North Korea has sought to modernize its fleet, but these upgrades have been modest. While the ballistic missile submarines and the submarine-marine launched ballistic missiles (SLBMs), have been important efforts, the KPAN has been last in line among the services for defense resources. But there are signs this may be changing with important implications for Korean security.

During a speech to mark Navy Day on 29 August 2023, Kim Jong-un declared: “Owing to the reckless confrontational moves of the US and other hostile forces, the waters off the Korean Peninsula have been reduced to the world’s biggest hardware concentration spot, the most unstable waters with the danger of a nuclear war” (KCNA 2023a). Referencing the Camp David Summit of Japan, South Korea, and the United States, Kim called the participants a “gang of bosses” and challenged the KPAN to maintain readiness and “a constant combat alertness” while “radically improving the modernity and fighting capacity of the Navy.” In February 2024, Kim visited the Nampo shipyard and called for the construction of new warships because they were crucial to the country’s defense. Paraphrasing Kim’s remarks, KCNA reported Kim asserting that strengthening the Navy “presents itself as the most important issue reliably defending the maritime sovereignty of the country and stepping up war preparation” (Kim 2024). Finally, in September 2024, Kim Jong Un visited the construction site of a new naval base confirmed: “we are soon to possess large surface warships and submarines which cannot be anchored at the existing facilities”; modernizing the KPAN is an “urgent task” and the need “to build a modern and multifunctional naval base is a process of key importance in developing the naval force into a powerful service in conformity with the regional security environment” (KCNA 2024).  

What to make of these statements? After years of focusing on the development of nuclear weapons and ballistic missiles, is North Korea adding the improvement of naval capabilities to its list of priorities? Though the answers are uncertain, there are several key questions to consider. What goals may underlie this strategic shift? What are the likely lines of effort for a naval modernization program? What is the likelihood of the DPRK succeeding in its modernization plans? And what are the implications for Korean security?

North Korean Naval Modernization

KPN modernization can be roughly broken down into two categories: naval assets linked to its nuclear deterrent and conventional naval capabilities. Both are concerning but for different reasons.

The chief modernization effort for the KPAN has been the development of a ballistic missile submarine capable of launching nuclear warheads. In 2016, North Korea revealed the 8.24 Yongung, a Sinpo-class submarine with one or two vertical launch tubes in a modified conning tower for launching SLBMs. In September 2023, Kim Jong-un revealed another, more advanced Sinpo-class submarine, the Hero Kim Kun Ok calling it a “tactical nuclear attack submarine.” The boat is a modified Romeo-class submarine with ten vertical tubes, four large tubes for SLBMs and six smaller tubes for cruise missiles, all presumably capable of carrying a nuclear warhead (Mizokami 2021). With the “tactical” designator, the SLBMs are likely short-range missiles. During the ceremony that revealed the Hero Kim Kun Ok, Kim Jong Un proclaimed the new submarine an “underwater offensive means of naval force” and “the first entity … in the great cause of building an advanced maritime power” (KCNA 2023b). Thus, “there is no room to step back in the drive for the expansion on the naval vessel-building industry as it is the top priority task to be fulfilled without fail” and stressed the need to “enhance the modernity of underwater and surface forces and push forward with nuclear weaponization of the Navy in the future” (KCNA 2023b). Though the Hero Kim Kun Ok is an improvement, it will still be a noisy vessel and relatively easy track with limited range that will restrain its ability to conduct deep-water operations. It is not clear how close the boat is to being operational.

In tandem with these efforts, North Korea has been working on the Pukguksong-1 (KN-11), an SLBM that has been flight tested on five occasions beginning in 2014 from several platforms and in 2019, tested another variant, the Pukguksong-3 (KN-26) from a submerged launch platform. The overall status and capability of these missiles is uncertain.

A few weeks prior to the launch of the Hero Kim Kun Ok, Kim Jong-un visited an East Sea naval base to observe a test of what was called a “strategic cruise missile” from a new surface vessel, an Amnok-class corvette. The “strategic” label likely means it is intended to be nuclear-capable, and the test was also significant for the revelation of the new corvette. As North Korea’s most advanced surface combatant, the Amnok corvette has a reduced radar cross section along with the KPAN’s most advanced weapons systems and sensors. Yet according to one source, these features are still obsolete compared to Western technology and appear to be cobbled together from decommissioned North Korean and Chinese ships (Misopoulos 2023). Accordingly, this assessment concluded: “as a surface combatant, the Amnok-class corvette isn’t really noteworthy. It is just a corvette with outdated and poor sensor and weapons fit. … [the ship] is a game changer however in that it brings the unexpected capability to strike South Korea and Japan at stand off range with nuclear typed [sic] land attack cruise missiles” (Misopoulos 2023).

Another nuclear-capable weapon system appeared in March 2023, the Haeil underwater drone. Korean for “tsunami”, the Haeil replicates the Russian Poseidon torpedo that is a large, “mega torpedo”, nuclear-armed and autonomous. KCNA stated: the Haeil “can be deployed at any coast and port or towed by a surface ship for operation” (Ng 2023). The Haeil was tested on two more occasions, the last in January 2024 after North Korea-Russia relations took off leading to the possibility that Russia may have provided some degree of technical assistance to the program. However, the extent of Russian help along with the exact level of capability of this weapon is again uncertain.

Kim Jong-un has also indicated his intention to grow other elements of the KPAN noting in his 2023 Navy Day address that “rapidly developing the naval force has become a very urgent issue in view of the enemies’ recent aggressive attempts and character of military actions.” (KCNA 2023a). The current KPAN surface fleet includes over 370 coast patrol ships, 265 amphibious assault craft and 20 mine warfare boats. The only large surface combatants are 2-4 frigates with plans to build a few more but no class of ships larger than these vessels. Most of the fleet consists of small, high-speed ships like guided-missile and torpedo boats along with smaller patrol vessels with all limited to coastal operations. The KPAN faces the same challenges as other branches of the North Korean military due to a shortage of fuel and spare parts that raise serious questions about training and readiness.

North Korea has also undertaken measures to improve its conventional surface navy though they have been more modest. These efforts were triggered by North Korea’s defeat at the First Battle of Yeonpyeong Island in June 1999 that may have been a wakeup call as the KPAN was likely surprised with how poorly their antiquated weapons and targeting systems fared against more modern ROK ships (Roehrig 2023, 136-38). Some of the KPAN’s patrol vessels have received upgraded weapons systems that allow faster rates of fire and improved targeting systems including more modern radar and sensors. The KPAN has also acquired several new fast attack boats that include catamarans, Very Slender Vessels (VSV), and hovercraft. The Amnok corvette noted earlier along with the Tuman-class corvette also represent improvement in its conventional navy and along with the planned frigates, provide the fleet with greater anti-submarine warfare (ASW) capability to address South Korea’s growing submarine force. Thus, Mitzer and Oliemans (146) caution that “the lack of public information on the KPAN’s capabilities have given it the reputation of solely operating outdated ships, as well as lacking the funding to maintain what inventory it has. Not only is this stereotype unsound, the often-echoed presumption that the KPAN is incapable of introducing new technologies is also incorrect.”

North Korea’s Intentions?

States can have several motives for maintaining navies including to win wars, deter aggression, protect their maritime commercial interests and to project power. Kim Jong-un has argued the need for a stronger navy in general terms but there are likely more specific reasons for his intent to move in this direction. First, it is clear that developing an underwater component to North Korea’s nuclear capability is the top priority. The Hero Kim submarine’s ability to launch nuclear-tipped ballistic and cruise missiles along with the Haeil nuclear-armed underwater drone gives Pyongyang a larger variety of nuclear launch platforms. Tactical nuclear weapons on the Amnok corvette add further to a broader maritime component of nuclear deterrence that complicates ROK-US defense planning and increases the survivability of North Korea’s nuclear deterrent.

Modernization of the conventional portion of the fleet is likely viewed as important to better defend North Korea’s coastal waters. North Korea already has an “area denial” capability from shore-based missile and rocket batteries but more ships armed with longer range anti-ship missiles help to create a wider homeland defense zone, particularly in response to growing South Korean naval capability and increased Japan-ROK-US maritime cooperation. These capabilities may also allow future collaboration, possibly exercises, with Russian and Chinese navies that would do little for Moscow and Beijing but would boost DPRK prestige and operational skill.

In addition, should war break out, the Korean theater will likely be dominated by the ROK/US Navies. While greater KPAN capability would be unable to challenge this sea control, more capable surface ships, underwater drones, and submarines, whether conventional or nuclear-armed would have a better chance of disrupting the flow of forces into Korea and disabling ports like Busan and others for resupply efforts.

Finally, defense analysts have also been watching North Korea’s naval acquisitions for indications that Pyongyang is seeking to increase the KPAN’s ability to project power. The number of amphibious assault vessels and landing craft that could undertake operations against the islands along the Northern Limit Line have been a concern. Yet North Korea’s existing naval capability along with many of the modernization efforts and new bases appear destined for the East Sea for more power projection here rather than in the West Sea. 

Challenges

While these initiatives provide some improvement to KPAN capabilities and Kim Jong Un’s recent statements point to a renewed determination to build up his Navy, significant obstacles remain. First, all states face the challenge of limited resources and North Korea is particularly hard-pressed in this regard. Despite spending a large portion of state resources on defense budget, Pyongyang still has spending constraints on what it can accomplish given its many other priorities. North Korea has adopted a strategy of focusing on asymmetric capabilities because it cannot match ROK defense acquisitions. Though North Korea has often demonstrated that it can come up with the necessary resources despite sanctions, it must ultimately make choices. Expanding and modernizing the KPAN to the degree that it will make much difference is a costly proposition and its not clear if funding will match Kim’s rhetoric for growing naval capability, especially if these capabilities are not tied to nuclear weapons. 

Second, even if North chose to devote the needed resources, there are major questions about its ability to build and acquire what is needed. The DPRK has limited shipbuilding capacity and the advanced technology needed for new vessels as well as to modernize older ships. Though sanctions enforcement is waning, it will be difficult to acquire the needed technology for advanced weapons systems. North Korea’s growing ties with Russia may provide a source for some of these items, but it’s not clear that Moscow will be willing to part with the necessary technology that would make a difference.

Conclusion

The direction and intensity of North Korea’s naval modernization bears watching but it is unclear how far and how quickly this effort will go. The priority is likely to remain the ballistic submarines and other platforms that can contribute to Pyongyang’s nuclear deterrent. North Korea has long pursued asymmetric capabilities to offset the difficulty it has in keeping pace with ROK naval development. While many questions remain regarding North Korea’s ability to build sufficient numbers of submarines and develop the necessary operational skill for a secure second strike capability, Pyongyang has surprised in the past and will continue this work in earnest. The scope and scale of conventional modernization is even more uncertain. Though Kim has talked about growing the KPAN, these efforts are likely to remain more modest with slow and incremental improvements to existing vessels and construction of a few new ships. Time will tell how far North Korea is able to progress toward these goals but it is clear that Kim Jong-un has decided to place more importance on the role of naval power in DPRK defense strategy.