The New North Korean Threat

Among the more overlooked geopolitical developments in 2022 was North Korea’s nuclear weapons program. During the year, it logged nearly 100 missile tests, a record for the country; several of them involved weapons of extraordinary range and potency. In November, the regime launched a Hwasong-17, an intercontinental ballistic missile that can carry multiple warheads and is capable of reaching the United States. A month later, North Korean leader Kim Jong Un personally oversaw the test of a powerful solid-fuel rocket engine—a crucial new capability for the country because solid-fuel rockets can be fired more quickly than liquid-fuel ones and are harder to detect and preempt.

Yet despite these developments, North Korea has not been a major focus for the United States in recent years. Although the country has posed a growing threat since 2006, when it first tested an atomic bomb, international efforts to slow down or stop its nuclear program have flagged. The last attempt by the United States to end the nuclear weapons program failed at the 2019 summit meeting in Hanoi between Kim and Donald Trump, and the Biden administration has not come up with any new ideas on how to achieve this. This is partly because the United States and its Western allies have been preoccupied by other pressing concerns, such as the war in Ukraine. But the West has also become, to some extent, inured to the North Korean threat.

This lack of attention is dangerous. Along with the accelerating number of tests, there are numerous other indications that Pyongyang’s efforts to build weapons of mass destruction (WMD) have been rapidly expanding and evolving. Developments over the past few months in particular suggest that the nuclear program is entering a new and more dangerous phase. The risk that a miscalculation by Pyongyang could lead to a conflict is growing, particularly given its lack of communication with Washington. All of these developments make clear the urgent need for the United States and its allies to enhance deterrence of the North Korean regime.

Armed and Dangerous

North Korea’s pursuit of solid-fuel missiles provides a startling indication of its current aims. All three ICBMs North Korea has tested so far—the Hwasong-14, Hwasong-15, and Hwasong-17—are liquid fueled. This is in accordance with the five-year plan set forth by the regime in January 2021 at its Eighth Party Congress, where it announced that it would soon be unveiling solid-fuel ICBMs that could be launched from both the sea and land. Pyongyang now appears to be making rapid progress toward that goal. Already, a series of new short-range ballistic missiles it has tested in recent years use solid fuel. It is now foreseeable that North Korea will conduct more solid-fuel engine tests on larger missiles. These include likely tests of a Pukguksong submarine-launched ballistic missile or a new solid-propellant ICBM. Kim’s sister Kim Yo Jong recently warned that the latter may be tested on a full-range trajectory toward the United States rather than on a lofted trajectory into the Sea of Japan, the destination of its previous ICBM tests.

In the coming months, North Korea could also unveil multiple independently targetable reentry vehicle (MIRV) technology, which will allow its missiles to frustrate U.S. missile defenses. The recently tested Hwasong-17 is designed to carry multiple warheads and could thus theoretically strike Manhattan and Washington at the same time.

North Korea is the only country that has threatened first use of nuclear weapons so explicitly.

As if these missile tests weren’t alarming enough, there are many indications that Pyongyang will soon conduct its seventh nuclear test. Such a test could be used to showcase a more compact tactical nuclear warhead for battlefield use—a weapon that would increase the threat North Korea poses to Japan and South Korea as well as to U.S. forces stationed in both countries. Satellite imagery has made clear, for example, that the Punggye-ri testing site, located in mountainous terrain north of Pyongyang and close to the border with China, is ready for such a detonation at any time. Testing a tactical nuclear warhead would also be consistent with Kim’s announced weapons development goals.

North Korea has already demonstrated its ability to deploy tactical nuclear weapons over the past year. In September and October, it conducted a series of tests of short-range missiles, with one simulating the launch of a nuclear missile from an underwater silo and another rehearsing the launch of nuclear warheads that could target airports in South Korea. But the regime has yet to demonstrate that it has developed a smaller warhead that could arm these missiles. It will need to do that soon if Kim intends to deploy this capability within his announced five-year timeline.  

In addition to rapidly enhancing North Korea’s WMD arsenal, Kim has also been lowering the threshold for its use. In September, North Korea announced five conditions under which it would launch a preemptive strike. Notably, these included not only when a nuclear attack on the country is imminent but also when its leaders believe that preparations may be underway for a nonnuclear strike on the North Korean leadership, a North Korean nuclear command structure, or important North Korean strategic targets. Pyongyang has also said it could use a nuclear weapon if it determines that it has no other way to prevent the expansion of a conventional war into one that would threaten the regime’s survival. Kim is clearly signaling that if a conventional, preemptive strike against the North is launched or even appears to be imminent, he reserves the right to respond with nuclear weapons. North Korea is the only country in the world that has threatened the first use of nuclear weapons so explicitly.

Along with its new policy for preemptive WMD use, the Kim regime has sought to cement its nuclear power status by declaring in September that it “will never give up” its nuclear weapons and that its weapons program is “irreversible” and “nonnegotiable.” In effect, Kim is asserting that North Korea will never again discuss denuclearization with the United States, even as it expands its nuclear forces and threatens a preemptive strike. This amounts to a destabilizing triple whammy.

Unconventional Threats

Although the United States and its close allies in Asia have watched Kim’s accelerating WMD program with growing concern, they have not yet mounted a response that can deter the North from its current path. Part of the issue is that Western policymakers and observers are not as concerned as they should be about recent developments. Some North Korea watchers, for example, have posited that the program is for defensive purposes only and that Pyongyang’s testing spree is simply a way to modernize its arsenal, allowing the regime to use it as leverage in future negotiations to win sanctions relief and other concessions. In this reading, the aim of the new first strike policy is merely to deter the United States from contemplating an attack on the regime. The logic of this argument is that Kim is not suicidal and knows that if he launches a first strike on the United States, it could lead to full-scale conflict and his own demise, as well as that of his regime.

Such reasoning, however, overlooks more unsettling possibilities. For a start, Kim may believe that through nuclear saber-rattling, he can achieve one of his main strategic goals, which is undermining the U.S.-South Korean alliance. He may calculate that even if he uses nuclear weapons preemptively against the South or U.S. bases in the region, the United States will not retaliate as long as his long-range ICBM force threatens the U.S. mainland. He may figure that Washington—particularly under a future isolationist president—will be unlikely to defend South Korea if by doing so it risks the incineration of American cities.

Moreover, even if Kim intends to avoid rather than initiate a conflict, his growing WMD program could lead to war. History provides ample examples—from World War I to the Cuban missile crisis—of situations in which a series of miscalculations led to or could have led to a catastrophic conflict. Imagine what would happen if a North Korean missile aimed at South Korean territorial waters were to strike South Korean fishing vessels, killing South Korean sailors. South Korean President Yoon Suk-yeol could order a limited retaliatory strike, precipitating further escalation into a wider conflict. This is hardly a far-fetched scenario: In 2010, tensions between the two countries dramatically ramped up after the North sank the South Korean naval corvette Cheonan and shelled South Korea’s Yeonpyong Island. Although Lee Myung-bak, then South Korea’s president, showed restraint under U.S. pressure after the attack on the Cheonan, the country’s forces responded with artillery fire after the shelling of the island. A future such confrontation could easily spiral out of control, especially in view of North Korea’s new first-strike policy.

71 percent of South Koreans now support acquiring nuclear weapons.

Nuclear and missile threats are not the only threats from the North the United States and its Asian allies need to be concerned about. The U.S. secretary of homeland security, Alejandro Mayorkas, said in October that North Korea has stolen as much as $1 billion worth of cryptocurrency and hard currency in the past two years to fund its nuclear program. To make up for the economic cost of international sanctions and the closing of the North’s border with China during the COVID-19 pandemic, the regime appears to have ratcheted up cyberthefts. In the future, North Korean hackers could use their cybersecurity capabilities for attacks as well as theft. Drones are yet another concern: on December 26, the North violated South Korean airspace by flying surveillance drones across the border for the first time in five years. Some of the drones entered the northern end of the 2.3-mile no-fly zone surrounding the presidential office in Seoul. That incursion prompted the South to scramble jets, fire warning shots, and fly its own drones into North Korean airspace. 

These developments are causing South Korea and Japan to reconsider their existing policies toward North Korea, given their vulnerability as nonnuclear states facing a nuclear-armed rogue regime. Until now, they have relied on a robust conventional defense posture while counting on the United States to use its nuclear umbrella to shield them from nuclear attack. In December, however, Yoon described what he called a “serious threat” from the North that could lead to a dangerous miscalculation and spark a wider conflict and stepped up his call for closer security cooperation with the United States and Japan. In early January, he said that South Korea needed to strengthen its defense capabilities and suggested that the United States should expand its “extended deterrence,” including joint exercises and planning involving U.S. nuclear assets, and initiate a more active information exchange.

In late December, South Korea’s National Assembly approved a 4.4 percent hike in defense spending for 2023, bringing Seoul’s total defense budget next year to about $45 billion. The increase includes funding for new preemptive strike capabilities and a $440 million plan to counter the North’s drones. President Yoon went even further in January, stating that if the North’s nuclear threat continued to grow, South Korea would consider starting its own nuclear weapons program or ask the United States to redeploy nuclear weapons on the Korean Peninsula. Yoon’s comments mark the first time since the United States withdrew its nuclear weapons from the South in 1991 that a South Korean president has publicly mentioned arming the country with nuclear weapons, an option that a large majority of South Koreans—71 percent, according to recent polls—support.

Meanwhile, Japan has made an unprecedented change in its own National Security Strategy in response to the increased threats from both North Korea and China. Under the plan unveiled by Japanese Prime Minister Fumio Kishida in mid-December, Japan will increase its defense spending by a whopping 26.3 percent this year and more than 50 percent over the next five years, shattering its decades-old doctrine of limiting defense spending to one percent of GDP. Japan also plans to acquire long-range counterstrike capabilities it has long shunned, including several hundred U.S.-made Tomahawk cruise missiles that could reach targets in both China and North Korea.

A Stronger Umbrella

Although the new approaches in Seoul and Tokyo are important steps for countering the North Korean threat, it is vitally important that both countries cooperate more closely with the United States. This could involve more joint military exercises like the ones held by South Korea, Japan, and the United States in October and November; computer simulations of a North Korean attack and drills; deeper intelligence sharing; and robust planning for the employment of the extended U.S. nuclear umbrella. The United States and South Korea should create a consultative group, bringing in both high-level security officials and unofficial observers to build greater support for sustained security cooperation and examine options for improving crisis management.

Washington should also take steps to strengthen its own security umbrella in the region. The United States should reaffirm its treaty-based collective defense commitments to both Japan and South Korea while also bolstering its regional deterrence and defense capabilities in a number of ways. These include augmenting missile defenses and rotating more nuclear-capable U.S. weapons systems into South Korea, such as B-52s and F-35s. As the Biden administration’s 2022 Nuclear Posture Review states, the United States will need to work more closely with South Korea and Japan to ensure “an effective mix of capabilities, concepts, deployments, exercises, and tailored options to deter and, if necessary, respond to coercion and aggression.”

But enhancing deterrence against North Korea is only one part of the puzzle. Working with Japan, South Korea, and other allies, the United States also needs to make it more difficult for Kim to access the hard currency he needs to fund his WMD program. Given its escalating tensions with Beijing, the Biden administration cannot count on China to enforce tough sanctions. By working with its allies, however, the United States can do more to disrupt North Korean cyber-heists. If the West is able to cut off more of Kim’s sources of revenue, it will not only create a significant barrier to his WMD program. It is also possible that such financial pressure could ultimately force Kim to the negotiating table because it would threaten his ability to dole out the favors needed to buy off the North Korean elite.

North Korea’s WMD program is growing at an alarming rate. South Korea and the United States must address the situation before it becomes destabilizing and the strategic balance tilts in favor of North Korea, at which point it will be far more difficult for the West to respond. Such a robust, coordinated effort will require deepening and expanding the U.S.–South Korean alliance and bringing South Korea into closer cooperation with Japan, Washington’s other major ally in the region. Putting this approach into play will require overcoming political opposition in South Korea and Japan and greater attention in Washington, where the focus is understandably on the war in Ukraine. But the security imperative is clear and pressing.