How Advanced Are North Korea’s Missiles?

Analysts (myself included) writing for 38 North, a program of the U.S.-Korea Institute at SAIS devoted to North Korea analysis, have been tracking North Korean missile development for many years. We are accustomed to seeing slow and intermittent progress: A test launch of a new missile every year or so, a few training exercises with older designs, and maybe some accompanying political bluster. The missiles in question were 1950s-era vintage Cold War designs modified to meet Pyongyang’s needs, and never really impressed anyone. When the North started testing nuclear devices in 2006, that also was done at a slow pace and with unimpressive performance.

Things change. In 2012, North Korea grabbed the headlines by parading mock-ups of advanced new missiles, and launched a satellite into low Earth orbit to show what they could do. Nuclear tests are more frequent and more consistent in performance. Since late 2014, North Korea has been testing new missiles half a dozen or more times a year instead of once or twice. They’ve been doing more ground testing as well, and unlike before they are showing us detailed imagery of some of those tests.

A decade ago, one could conclude that while North Korea could cause some degree of damage to the South with its stockpile of antiquated weapons, their pretension of being a real nuclear power exceeded their technical capability and would remain so for many years to come. Pyongyang seems intent on showing us that this is no longer the case. They are making a serious effort to upgrade their strategic arsenal, in an uncharacteristically public fashion, and they have achieved some undeniable technical successes along the way.

Given the timing, it is easy to ascribe this to Kim Jong-un making a bid for attention. It seems prudent to pay some degree of attention to the man waving about an arsenal of nuclear missiles, though with a skeptical eye to the possibility of deception. What are the real, present capabilities of North Korea’s strategic missile forces, and what is the future likely to bring?

Where Does North Korea Stand Today?

The first thing to understand about North Korea’s strategic weapons is that, while new missile development may grab attention, Pyongyang has plenty of old missiles that still work. And at this point it takes a particularly optimistic sort of wishful thinking to expect that they haven’t figured out how to build a nuclear warhead that will fit their existing missiles. As my colleague Jeffrey Lewis has described for 38 North, North Korea is past the point where everyone else was able to build their first lightweight bombs and missile warheads.

To deliver those warheads today, North Korea would most likely call on its force of Nodong and Scud-ER missiles. The Nodong, developed in the early 1990s, has been extensively tested and exported to both Iran and Pakistan. The Scud-ER was not revealed until last year, with the simultaneous launch of a three-missile salvo. Another salvo-firing test in early March was likely intended to demonstrate an operational warfighting capability.  Both missiles can reach targets anywhere in South Korea, and much of Japan. There may be more than 200 of these missiles in North Korea’s arsenal, though no more than two dozen nuclear warheads. This is not to say that they could launch a massive salvo of 200 missiles; there are probably no more than 40 of the transporter-erector-launchers (TELs) needed to fire them. But those TELs can play a shell game, hiding among North Korea’s thousands of tunnels and hardened bunkers while emerging to periodically launch missiles that might or might not be carrying nuclear warheads.

What Are They Trying to Accomplish?

With this capability already in place, why does North Korea feel the need to test new types of missiles? The most obvious reason is that the North Korean regime feels threatened by South Korea, Japan, and the United States, but their existing missiles can reach only two of those three foes. Pyongyang has made it clear that the United States is on its target list as well, and it intends to develop a long-range missile capability.

But North Korea’s old-fashioned Scud and Nodong missiles have limitations even when used against local targets. In particular, while nominally mobile they are limited to traveling by road, and will require probably an hour or more to prepare for launch. Such performance was good enough to survive allied “Scud hunting” efforts during the 1991 Persian Gulf War, but that was 25 years ago. Satellite, radar, and drone surveillance is far more capable now, as is the ability to launch precision strikes on short notice. Pyongyang is going to want missiles that can hide anywhere, not just at sites accessible by road, and they are going to want missiles that can be launched in minutes, not hours.

Finally, North Korea has goals that extend beyond nuclear destruction. National prestige is important to the Kim dynasty, and displays of both nuclear power and rocketry are one vector of that prestige. This extends beyond the purely military, as North Korea now has the beginnings of a space program and has voiced ambitions reaching as far as unmanned lunar exploration. Space launch vehicles use many of the same technologies as long-range missiles, so while North Korea’s space program may be following a separate path from its missile program we are going to have to closely watch them both.

So, building on the limited capabilities of their heritage Scud and Nodong missiles, we can expect North Korea to seek improvements along three vectors. First, increasing the mobility and responsiveness of their missiles to ensure the survivability of their deterrent and warfighting capabilities. Second, increasing the range of their missiles to directly threaten the United States. Third, demonstrating both powerful new missiles and a capable civilian space program for the sake of national prestige. In recent years, we have seen vigorous activity in all three areas.

Survivable Regional Forces

The surest indication of North Korea’s interest in more survivable regional forces is the new emphasis on solid-propellant missiles. Where corrosive liquid propellants generally must be loaded into missiles shortly before launch, solid fuel can be stored ready for use for years or even decades. Gone is the convoy of fuel tankers and specialized loading equipment, and an hour of preparation can be reduced to as little as five minutes. Solid motors are also more rugged than the thin-walled tanks of liquid propellants, and can be transported cross-country where liquid-propellant missiles are often constrained to roads.

North Korea started its shift to solid-propellant ballistic missiles about ten years ago, with the KN-02 “Toksan” short-range ballistic missile. Based on a 1980s Soviet design, this is a highly mobile, responsive, and accurate missile with a range of up to 200 kilometers. The KN-02 is probably tasked with direct support of front-line military forces using conventional or chemical warheads, but may have a limited role in delivering tactical nuclear weapons.

Last year, North Korea demonstrated a much larger solid rocket motor in ground tests. A few months later, the KN-11 or “Pukguksong-1” submarine-launched missile flew successfully under solid propulsion.  Now a land-based version called “Pukgugsong-2” has demonstrated the performance to deliver nuclear warheads across a range of over 1,000 kilometers. North Korea took care to show that the missile could be launched with minimal preparation and support from a heavy tracked vehicle.

These advances don’t make North Korea’s liquid-fueled Nodong obsolete right this minute, but the writing is on the wall. It may take another year or so of testing before the new missile can be deployed in the field, and some time beyond that for the North to build the dozens of TELs and hundreds of missiles they seem to feel makes for an adequate regional strategic force.

Another dimension in survivability is provided by North Korea’s submarine-launched missile program. We have seen evidence of this program since 2014, but early efforts involved a liquid-fuel missile that never worked properly. When the North shifted to solid propulsion, they scored their first real success on that front. They have, at least, a submarine-launched missile comparable to the first U.S. or Chinese SLBMs.

What they do not have, really, is a submarine to launch it. Their single Gorae-class submarine is an experimental testbed, not an operational weapon. A follow-on design may have begun construction in late 2016; the earliest it could plausibly enter service would be the end of 2018.  And let’s be clear: North Korea can, at most, build small diesel-electric submarines carrying perhaps three to five missiles, survivable only if they operate under the protection of other North Korean naval forces. This is a regional rather than a global threat.

Nonetheless, by the end of this decade the threat to targets in South Korea and Japan will come largely from a mix of land- and sea-based missiles with sufficient mobility to remain concealed from allied attack while ready to launch their own attacks on a few minutes’ notice. Most of the warheads will still be conventional, but probably several dozen will be nuclear. The ability to launch coordinated salvos of missiles from land, and to fire submarine-launched missiles from unexpected directions, will challenge allied missile defenses.

Coming to America

Until recently the only North Korean missile even potentially capable of reaching U.S. territory was an obscure design called the “Musudan,” and it could only threaten the island of Guam. The Musudan isn’t much of a threat. Based on an old Soviet submarine-launched missile, the Musudan was modified for mobile land basing and increased range but for over a decade after its deployment was never tested. People seriously considered the possibility that it was simply a hoax. Last year Pyongyang gave us a fast-paced series of tests that showed the Musudan was no hoax, but with only one clear success in eight attempts it lacks the performance and reliability to serve as a credible deterrent. While North Korea may not abandon the Musudan entirely they are unlikely to invest much more effort in it.

Nor do they need to, as they appear to have a much more formidable capability under development in the form of their KN-08 and KN-14 mobile ICBMs. When mock-ups of the KN-08 were first paraded through Pyongyang in 2012, they also were suspected of being a hoax. Every subsequent development has pointed toward this being a serious program. While neither missile has yet flown, North Korea has released images of a ground test of the missile’s engines, more powerful and efficient than anything North Korea had shown before.

The KN-08 missile is a three-stage design that, with the new engine, is predicted to have sufficient range to cover most of the continental United States but to have low reliability. The KN-14 appears to be a two-stage design using the same engines but a more advanced structural design; this would likely result in greater reliability but limit the range to U.S. west coast targets. It is not clear whether the KN-14 has replaced the KN-08 in North Korea’s strategic planning, or whether the more complex three-stage missile will be kept on the table to threaten, for example, Washington DC.

It is important to note that neither of these missiles exists at present as anything more than mock-ups and components undergoing ground testing. They might, in principle, be ready to begin flight testing today, but North Korea has generally lacked the resources to conduct aggressive test programs for many different missiles in parallel, and for the moment they seem to be focused on shorter-ranged systems. It would be surprising if they conducted their first ICBM test this year.

It would be even more surprising if their first test succeeded. North Korean missiles almost always fail on the first test, and a missile this complex will require multiple flight tests over a period of several years to reach operational status. North Korea can probably make the KN-08 or KN-14 work if they persevere, as they did with their Unha-3 space launch. But they cannot do it quickly, and probably will not have an operational ICBM before 2020.

If and when they do, it will be a very limited capability. The missiles will be available in limited numbers, and will probably never be very reliable. They have only six Chinese-built TELs capable of launching such ICBMs, and more will not be forthcoming. While nominally “mobile,” these missiles will be even more cumbersome than the Nodong – limited to paved roads and prepared sites, traveling with a convoy of dozens of support vehicles and requiring hours to prepare a launch. An ICBM based on their new solid-propellant technology would be a far more robust system, but that is at least a decade in the future.

Reaching for the Stars

North Korea launched its first satellite in 2012. A follow-on vehicle was launched in 2016. As far as we know, both of these satellites tumbled out of control shortly after launch. Still, launching satellites of any type puts North Korea in a club almost as exclusive as that of the nuclear powers. They have openly stated that they plan to do much more, even to the extent of launching an unmanned lunar probe sometime in the next decade.

The North Korean space program has in the past has been closely tied to their missile development program – so much so that when we first saw what would become their first satellite launch vehicle we assumed it was a prototype ICBM and gave it the code name “Taepodong-2.” While this rocket, properly known as the “Unha-3,” used many of the same technologies as North Korea’s missiles and no doubt served as a valuable learning experience, we have since learned that the Unha is optimized for launching satellites, not warheads.

North Korea’s space and missile programs seem to be on diverging trajectories. For missiles, North Korea is focusing on relatively small and mobile systems for survivability, and on solid propellant for all but the largest systems. North Korea’s space launch systems are entirely liquid fueled and tied to fixed launch sites. The Unha-3 itself appears to be a transitional design; a recent expansion of North Korea’s satellite launch facility and ground testing of a large liquid-fueled engine support claims that a much larger “Unha-9” will soon enter service. Such a rocket would be too large and cumbersome, and too dependent on fixed launch facilities, to be a viable weapon – it would not be survivable in wartime.

Pyongyang has a long road ahead in the development of reliable and useful satellite technologies, never mind a lunar lander. Some of their ambitions in space could have a military dimension; imaging satellites might find targets for missiles, for example. But these potential capabilities shouldn’t be confused with the actual development of missiles. If satellites are to compete with missiles for scarce development resources in North Korea, we might want to quietly encourage the less overtly hostile space program.

Where Will This End?

There are no easy options for restraining North Korea’s nuclear ambitions. The regime has made it quite clear that they consider a strong nuclear deterrent to be vital to their national security. They might be willing to accept constraints on nuclear or missile testing in exchange for other security guarantees, but they will not be persuaded to give up their nuclear deterrent entirely. Nor are they as dependent as they once were on foreign partners for nuclear and missile technology. They are not entirely self-sufficient in this area, but what little they do need to import can be obtained via black or grey markets. Economic sanctions won’t save us, even if we convince China to fully join the effort.

As a military response, the United States maintains some capability to intercept the sort of ICBMs Pyongyang is likely to develop, but the success rate in test is barely 50 percent. Regional missile defenses are more robust, particularly with the impending THAAD deployment to South Korea, but the regional threat is proportionately larger. Missile defense can mitigate the damage in wartime, but it won’t eliminate the threat. And as highly mobile solid-propellant missiles are deployed on land and sea, preemptive strikes against North Korea’s strategic forces will not be a reliable option.

By the end of this decade, North Korea will likely have a robust capability for delivering nuclear or conventional strikes against targets in South Korea or Japan. Instead of a spasm of violence leading to mutual destruction, Pyongyang’s survivable, responsive missiles will give them the option of weathering an allied attack and offering a calibrated response. Purely military targets may include allied ground forces invading the North, key air bases and logistical centers, and ports bringing in U.S. reinforcements.

More important are the political targets, and it is here that the next decade’s ICBM capability will be a game-changer. North Korea may be able to fight a nuclear war, but they cannot win one against the combined forces of the United States, Japan, and South Korea. For the regime to survive, it must prevent those allies from uniting against it. If it can separately threaten each of them with nuclear attack, how solid will the alliance be? Would the United States sacrifice San Diego to save Seoul? If Yokohama or even Tokyo were threatened, might Japan declare neutrality and close its vital ports and airbases to the United States?

These are hard questions, but Pyongyang’s increasing technical capabilities will force us to address them.