North Korean leader Kim Jong Un walking near a reported "new type" of intercontinental ballistic missile, North Korea, March 2022
North Korean leader Kim Jong Un walking near a reported intercontinental ballistic missile, North Korea, March 2022
Korean Central News Agency / Reuters

In the early months of 2022, as the world was transfixed by Russian President Vladimir Putin’s war on Ukraine, North Korean leader Kim Jong Un seemed to sense an opportunity. Since the invasion began, he has tested a slew of ballistic missiles, including hypersonic and long-range weapons, with relatively little international scrutiny. Kim’s objective is clear: he aims to develop weapons capable of overwhelming U.S. national missile defense systems. U.S. President Joe Biden’s national security team has been understandably preoccupied with Ukraine, but North Korea’s nuclear missile technology is rapidly advancing and demands urgent attention. Absent a change in U.S. strategy or an unexpected diplomatic breakthrough, Kim could eventually achieve his goal of being able to strike the United States with a nuclear-tipped intercontinental ballistic missile, with grave implications for U.S. and international security.

But Washington’s attention currently lies elsewhere. Biden’s 2022 National Defense Strategy, which has so far been released in its entirety only in classified form, singles out China as “the pacing challenge” and designates Russia as an additional, though secondary, priority. Concentrating minds and resources on these great-power rivals makes plausible sense, given the capacity of these countries to threaten the security and interests of the United States and its allies as well as broader global stability. The economic and security consequences of Russia’s invasion of Ukraine across Europe and throughout the world have only made this threat more apparent. But the United States must also make room in its top national security priorities to address an enormous—and mounting—security problem that is emerging elsewhere: North Korea is on the cusp of achieving the capability to hit the U.S. homeland with nuclear-tipped missiles. This development not only endangers the United States but could also imperil the U.S.-led alliance system in Asia by stirring doubts about the credibility of U.S. extended deterrence—a central element of long-standing U.S. security guarantees to its regional allies involving Washington’s promise to defend them from external attacks using, as U.S.-South Korea policy documents describe it, the “full range of U.S. defense capabilities, including nuclear, conventional, and missile defense capabilities.” It also gives Pyongyang new means to intimidate and coerce South Korea and Japan directly. If Washington hopes to maintain peace and stability in the Indo-Pacific, much less the world, it must confront North Korea’s ballistic missile program, and take immediate steps to contain it, before it is too late.

CHEAP MISSILES, COSTLY DEFENSES

For more than two decades, the world has known about North Korea’s efforts to develop nuclear-tipped missiles that could target the U.S. homeland. As long ago as 1998, Pyongyang conducted its first test of an intermediate-range ballistic missile known as Taepodong-1; and in 2006, it conducted its first nuclear test. But for U.S. residents, this news was generally accompanied by some comforting realities: North Korea had many difficult technical hurdles to clear before people in Los Angeles, New York, or other major U.S. cities needed to worry about Pyongyang potentially targeting them with nuclear warheads. For a time, these hurdles seemed potentially insurmountable, and the Western media frequently mocked North Korea’s seemingly blundering missile ambitions. Over time, however, Pyongyang has managed to clear one technical hurdle after another. With China’s and Russia’s help, it has been able to evade sanctions and gain access to international markets, attaining the resources and missile technologies it needs—many of which are now decades old and commercially available. It has designed a nuclear weapon small enough to fit inside the nose of a missile; it has built missiles capable of reaching the U.S. mainland; and it is believed to have developed reentry vehicles that can survive the intense heat and pressure of reentering the earth’s atmosphere when a ballistic missile is in its terminal phase, in order to carry nuclear warheads to their target. All these innovations bring North Korea ominously close to posing a direct nuclear threat to the United States.

At present, Pyongyang may be only a few more missile launchers away from having the capacity to defeat U.S. national missile defenses. As the international security expert Ankit Panda testified in June 2021 before the U.S. Senate Armed Services Committee, Pyongyang is estimated to have 10 ICBM launchers, while the United States has 44 ground-based interceptors capable of obstructing them before they reach their targets. The U.S. system is currently designed to use four interceptors to target each North Korean reentry vehicle, meaning that Pyongyang will require only a couple of additional launchers to theoretically overwhelm current U.S. missile defense capabilities. Although North Korea is building its ICBM threat using cheap technology dating back to the 1970s, the United States must invest in expensive, cutting-edge missile defenses if it hopes to provide an effective shield against these weapons. This is a numbers game that is stacked against the United States: even if Washington carries out its plan to deploy 20 more interceptors by the end of the decade, these additional defenses can be met with further North Korean launchers and countermeasures.

Washington could conceivably improve this equation by allocating three interceptors per reentry vehicle rather than four, which would allow U.S. defense systems to attempt to intercept more incoming reentry vehicles. But North Korea’s current efforts aim to wipe away even this potential advantage. Specifically, North Korea’s new Hwasong-17 ICBM, which many believe was tested in a failed launch near Pyongyang on March 16, may be large enough to carry multiple reentry vehicles that could include three or four nuclear warheads or a combination of real warheads and decoys. If North Korea were to launch multiple Hwasong-17 ICBMs, the technical challenges posed for U.S. missile defenses in intercepting the higher number of incoming warheads—and discerning actual warheads from decoys—would increase significantly. Development of other legs of the nuclear triad—which would include nuclear-missile-armed submarines and aircraft with nuclear weapons, in addition to land-launched nuclear missiles—would likewise shift the advantage back to Pyongyang before long.

A CREDIBLE THREAT

Putin’s war in Ukraine, in addition to destabilizing European security and upending the global economic order, has heightened the nuclear threat from North Korea in three significant ways. First, Moscow’s unprovoked attack on a sovereign European country—specifically one that renounced the nuclear weapons it inherited from the Soviet Union at the end of the Cold War—has, in Pyongyang’s view, underscored the necessity of nuclear weapons to deter any potential aggression. As the regime sees it, if North Korea were to renounce its nuclear program, it would, like Ukraine, be significantly more vulnerable to invasion. Second, Putin’s nuclear saber rattling and threats of an atomic confrontation with any NATO country that seeks to make a military intervention in Ukraine may give Kim Jong Un the idea that a first-use declaration, or reserving the right to use nuclear weapons first in battle, could deter U.S. intervention in the event of an armed conflict with South Korea. And third, if Putin actually uses tactical nuclear weapons in the war to create new advantages in specific battlegrounds in Ukraine, this could bolster Kim’s own stated desire to develop a battlefield nuclear weapons capability that could be launched over shorter distances and used on smaller targets like facilities or troops in South Korea, providing greater flexibility than larger nuclear weapons and greater destructive power than conventional weapons.

Kim aims to develop weapons capable of overwhelming U.S. national missile defense systems.

North Korea’s recent flurry of missile tests indicates that it is inching closer to being able to credibly threaten U.S. cities with nuclear weapons. Since the start of 2022, North Korea has carried out 13 missile tests, ranging from short-range hypersonic missiles to an intermediate-range ballistic missile to an intercontinental ballistic missile. This dramatic increase in testing has advanced the goals that Kim laid out for North Korean weapons development in unusual detail during the state’s Eighth Party Congress in January 2021. As he stated at the time, these aims include research focused on “perfecting the guidance technology for multi-warhead rocket [sic],” efforts to attain “an advanced capability for making a preemptive and retaliatory nuclear strike by further raising the rate of precision good enough to strike and annihilate any strategic targets within a range of 15,000 kilometres [sic] with pinpoint accuracy,” and developing “solid-fuel engine-propelled inter-continental underwater and ground ballistic rockets.” These aims—and North Korea’s advancement toward them—should raise major alarm in Washington, as their attainment would spell a major threat to U.S. and regional security.

In the weeks ahead, the world should expect to see further missile testing in North Korea, and perhaps even the first nuclear detonation since 2017. The war in Ukraine has provided a convenient cover for Pyongyang, as the United States remains consumed by Russia’s aggression. Even if Washington were to turn its attention toward North Korea, the close alignment of Beijing and Moscow and their unwillingness to condemn Pyongyang through the United Nations Security Council has stymied any collective international action to curb Kim’s nuclear program. Indeed, North Korea’s last ICBM test in March should have triggered further petroleum export sanctions under an existing UNSC resolution, but Chinese and Russian opposition prevented the UNSC from imposing sanctions or taking any other punitive actions. Meanwhile, the deterioration of relations between Seoul and Tokyo, driven by issues ranging from trade disputes to troubled historical dynamics, have hurt Washington’s ability to conduct trilateral military exercises and coordinate policy with its two key allies in the region. And internally, North Korea is dealing with challenging economic and health crises that also provide new incentives for the regime to glorify its military program, which can help to increase loyalty and morale among the population during periods of material hardship.

MORE IRON DOMES

North Korea may seek to develop specific capabilities in upcoming tests, including the successful deployment of multiple reentry vehicles which are key to frustrating U.S. and allied missile defenses; lighter and smaller nuclear warheads, which could be loaded individually on smaller missiles or in clusters on single ICBMs; submarine launched ballistic missiles (SLBMs), which would build the second leg of a potential North Korean nuclear triad; and, potentially, air launched nuclear cruise missiles, which would complete said triad. Pyongyang has already demonstrated a resolute determination to pursue these advancements: despite the regime’s dire economic straits, North Korea has scoured markets to acquire technology to test an SLBM, first from a submerged platform, and then later from a ballistic missile submarine.

There is no silver bullet to stop further North Korean advances in these areas. Diplomacy has reached a dead end, as Pyongyang has failed to respond to the Biden administration’s repeated offer to meet “without preconditions.” Kim will likely continue to avoid negotiations for at least the remainder of 2022, as the country progresses toward the technical milestones that he laid out at the Eighth Party Congress.

Yet some steps could put the United States and its allies in a significantly stronger position to address the growing North Korea security challenge. For instance, the United States could accelerate its planned deployment of 20 additional interceptors using Next Generation Interceptor (NGI) technology—currently slated for 2028—which would potentially enable single interceptors to target multiple objects and discriminate between warheads and decoys. Although, as noted, concentrating efforts on this interceptor-to-launcher one-upmanship is not a sound long-term strategy, it is essential amid North Korea’s current acceleration of its missile program, as it would strengthen U.S. national missile defenses while enhancing the credibility of U.S. security pledges to provide extended deterrence to its allies in the region. The United States should also increase its investment in other new technologies such as boost-phase defense systems, which target missiles in their earliest stage of flight. These systems are still in a nascent stage of development and involve a number of operational challenges, but their development would help Washington move away from its legacy national missile defense system, which is built around outdated assessments of North Korea’s missile threat from the 1990s, and which assume defending only against a handful of North Korean missiles based on rudimentary technology.

The war in Ukraine has provided a convenient cover for Pyongyang.

Within the region, the United States and South Korea should revitalize a comprehensive counter-missile strategy that would entail detecting and defending against North Korea’s missiles and launchers, disrupting the capabilities that allow North Korea to repeatedly fire its missiles, and destroying the missiles and launchers themselves. This would require new investments in sensors, intelligence and surveillance technology, advanced command and control infrastructure, and other weapons systems that would significantly enhance regional allies’ ability to stay ahead of North Korea’s technological advances.

Washington should also invest in equipping allies in the region with additional defense weapons and systems. Biden should support Seoul’s enhancement of its own capabilities to counter missiles from North Korea, consistent with incoming South Korean President Yoon Suk-yeol’s plans to deploy a new missile defense battery known as Terminal High Altitude Air Defense to cover Seoul and to accelerate work on South Korea’s interceptor systems, including SM-3 ship-based defenses and an artillery interception modeled after Israel’s Iron Dome, designed to protect the country’s population and critical infrastructure. Increasing U.S.-Japanese-South Korean coordination on missile defense is another critical step, albeit one that will require Yoon to abandon South Korea’s pledge to China under his predecessor, Moon Jae-in, not to integrate South Korea into a regional missile defense with the United States and Japan.

Lastly, despite Pyongyang’s unresponsiveness, the United States should continue to seek avenues of diplomacy with North Korea to achieve a permanent ban on missile tests. This shift in focus from North Korea’s nuclear weapons to its missile program is becoming more urgent as Pyongyang edges closer to being able to penetrate U.S. national missile defenses.

NOT-SO-GREAT POWERS

Taking on the North Korean missile threat will require a strong dose of pragmatism. Even a proactive and coordinated campaign in concert with U.S. allies in the region will not stop North Korea’s nuclear and missile efforts in their tracks—in fact, it is doubtful that anything could. Nor will these measures fix the long-standing technological and strategic challenges that plague legacy U.S. national missile defenses, including the difficulties associated with mid-course intercepts, overnight. Critics may even argue that a U.S. effort to ramp up its own missile defenses and that of its allies could create the worst of two worlds: a new arms race with China that does not solve Washington’s North Korea problem.

Beijing and Moscow will argue, as they have in the past, that any upgrades to the U.S. national missile defense system designed to address missile threats from North Korea will make their countries less secure by upsetting the great-power balance. They will point to U.S. missile defense enhancements as excuses to continue expanding their own nuclear and missile capabilities, as they have since the system was first developed as a response to the North Korean ICBM threat in the early 2000s.

Washington needs to focus on this smaller power, which is determined to achieve great-power-level nuclear status.

These are not adequate reasons, however, for the United States and its allies to allow North Korea’s dangerous missile program to go unchecked. Washington needs to muster all of the resources at its disposal to fortify its position vis-à-vis a country that is resolved to threaten the United States’ homeland and weaken its alliances in Asia. The effects of a revised North Korean missile defense policy on relations with China and Russia should be considered, but they should not exclusively drive decision-making in Washington. The current infrastructure of the U.S. national missile defense system is no match for arsenals the size of Russia’s and China’s: the United States has and should continue to provide assurances that the system is not designed to destroy Chinese or Russian strategic deterrents, and there is no need to respond in kind.

Addressing Pyongyang’s advanced missile program is a unique challenge that will require a comprehensive and tailored response from Washington. If U.S. policymakers and defense planners remain absorbed by great-power conflict in Europe, they could find themselves witnessing the rapid emergence of the greatest nuclear threat that the United States has faced in generations. Even as the Biden administration deals with Russia’s war in Ukraine and China’s growing rivalry, it needs to sharpen its focus on this smaller power, which is increasingly determined to achieve great-power-level nuclear status—and which gets closer to that goal with each passing day.

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  • KATRIN FRASER KATZ is an Adjunct Fellow (non-resident) in the Office of the Korea Chair at the Center for Strategic and International Studies. She served on the staff of the U.S. National Security Council from 2007 to 2008.
  • VICTOR CHA is the D.S. Song-KF Professor of Government in the School of Foreign Service at Georgetown University and Senior Vice President at CSIS. He served on the U.S. National Security Council from 2004 to 2007 and was U.S. Deputy Head of Delegation for the Six-Party Talks.
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