- North Korea could have more than sixty nuclear weapons, according to analysts’ estimates, and has successfully tested missiles that could strike the United States with a nuclear warhead.
- It has the world’s fourth-largest military, with more than 1.2 million personnel, and is believed to possess chemical and biological weapons.
- Despite UN Security Council sanctions and past summits involving North Korea, South Korea, and the United States on denuclearization, Pyongyang continues to test ballistic missiles.
The United States and its Asian allies see North Korea as a grave security threat. North Korea has one of the world’s largest conventional military forces, which, combined with its missile and nuclear tests and aggressive rhetoric, has aroused concern worldwide. But world powers have been ineffective in slowing its path to acquire nuclear weapons.
While it remains among the poorest countries in the world, North Korea spends nearly a quarter of its gross domestic product (GDP) on its military, according to U.S. State Department estimates. Its brinkmanship will continue to test regional and international partnerships aimed at preserving stability and security. Negotiations on denuclearization have remained stalled since February 2019.
What are North Korea’s nuclear capabilities?
The exact size and strength of North Korea’s nuclear arsenal are unclear. However, analysts say Pyongyang has tested nuclear weapons six times and developed ballistic missiles capable of reaching the United States and its allies Japan and South Korea.
Pyongyang could have between twenty and sixty assembled nuclear weapons, according to various estimates by experts. U.S. intelligence officials estimated in 2018 that North Korea has enough fissile material—the core component of nuclear weapons—for sixty-five weapons, and that every year it produces enough fissile material for twelve additional weapons. A 2021 RAND Corporation report projected that North Korea could have around two hundred nuclear weapons and hundreds of ballistic missiles stockpiled by 2027. The regime possesses the know-how to produce nuclear bombs with weapons-grade uranium or plutonium, the primary elements required for making fissile material.
North Korea has conducted six nuclear tests, first in October 2006 and then in May 2009 under former Supreme Leader Kim Jong-il. Under Kim Jong-un, Kim Jong-il’s son who assumed power in late 2011, the nuclear program markedly accelerated. Kim has directed four nuclear tests—in February 2013, January and September 2016, and September 2017—and more than 125 missile tests, far exceeding the number of trials conducted under his father and grandfather, North Korea’s founder, Kim Il-sung.
With each test, North Korea’s nuclear explosions have grown in power. The first explosion in 2006 was a plutonium-fueled atomic bomb with a yield equivalent to two kilotons of TNT, an energy unit used to measure the power of an explosive blast. The 2009 test had a yield of eight kilotons; the 2013 and January 2016 tests both had yields of approximately seventeen kilotons; and the September 2016 test had a yield of thirty-five kilotons, according to data from the Nuclear Threat Initiative, a Washington, DC-based nonpartisan think tank. (For comparison, the U.S. bomb dropped on Hiroshima in 1945, the first atom bomb, had an estimated yield of sixteen kilotons.)
The nuclear test carried out on September 3, 2017, was significantly larger, experts say, and indicated that the country has developed much more powerful bomb-making technology. Estimates from seismic activity led observers to conclude that the explosion likely exceeded two hundred kilotons. An explosion of such a size gives credence to North Korea’s claims of having developed a hydrogen bomb.
North Korea has not conducted a nuclear test since then. In 2018, North Korea said it shut down its main nuclear-material production site, the Yongbyon reactor complex, following the country’s summits that year with the United States and South Korea. But in August 2021, the International Atomic Energy Agency (IAEA) reported that North Korea had again started producing fissile material at Yongbyon.
Some experts caution that it is only a matter of time before North Korea completes its nuclear force. “We’re going to have to learn to live with North Korea’s ability to target the United States with nuclear weapons,” said Jeffrey Lewis of the Middlebury Institute of Strategic Studies.
What missiles has North Korea tested?
North Korea has tested more than one hundred ballistic missiles with the ability to carry nuclear warheads, including short-, medium-, intermediate-, and intercontinental-range missiles and submarine-launched ones.
The regime successfully tested intercontinental ballistic missiles (ICBMs), each capable of carrying a large nuclear warhead, in July and November 2017. Pyongyang said that in its November test of the Hwasong-15 ICBM, the missile hit an altitude of 4,475 kilometers (2,780 miles), far above the International Space Station, and flew about 1,000 kilometers (590 miles) before landing in the sea off Japan’s coast. Analysts estimate the Hwasong-15 has a potential range of 13,000 kilometers (8,100 miles) and, if fired on a flatter trajectory, could reach anywhere on the U.S. mainland. American analysts and experts from other countries still debate the nuclear payload that North Korea’s ICBMs could carry, and it is still unclear whether the ICBMs have the capability to survive reentry. A confidential U.S. intelligence assessment from 2017 reportedly concluded that North Korea had developed the technology to miniaturize a nuclear warhead to fit its ballistic missiles.
Kim halted missile testing in late 2017 amid a thawing of relations with the United States and South Korea. But North Korea resumed testing in mid-2019, months after negotiations between Kim and U.S. President Donald Trump in Hanoi, Vietnam, broke down. Later that year, Pyongyang conducted an underwater launch of a ballistic missile, its first such test in three years.
Since then, North Korea has unveiled several new ballistic missiles. The first, shown during an October 2020 military parade, was an ICBM larger than the Hwasong-15. It has not been named or tested, but analysts say it could potentially carry multiple nuclear warheads or decoys to confuse missile defense systems. A new Pukkuksong-4 submarine-launched ballistic missile was also displayed in October 2020, and its successor, Pukkuksong-5, was unveiled in January 2021. Experts estimate the Pukkuksong-5 has a range of around 3,000 kilometers (1,864 miles), which would allow it to strike Guam. Experts say neither missile has been tested yet.
In 2021, Pyongyang tested short-range ballistic missiles that are solid fueled, advancing a technology that makes missiles easier to transport and faster to launch. In addition, it tested a more maneuverable long-range cruise missile, which can frustrate missile defense systems if launched in tandem with ballistic missiles. In September, North Korea for the first time test-fired missiles from a railcar launcher, which makes them less detectable by the United States and its allies.
There remain significant unknowns surrounding the accuracy of North Korea’s ballistic missiles. Observers have said that these missiles are usually inaccurate because of their reliance on early guidance systems acquired from the Soviet Union. However, some defectors and experts say North Korea has begun using GPS guidance, similar to that of China’s navigation system, raising questions about the provenance of the system and whether North Korea’s arsenal of missiles is more accurate and reliable than previously believed.
Have other countries aided North Korea’s nuclear program?
The program is predominantly indigenous but has received external assistance over the years. Moscow, for instance, assisted Pyongyang’s nuclear development from the late 1950s to the 1980s: it helped build a nuclear research reactor and provided missile designs, light-water reactors, and some nuclear fuel. In the 1970s, China and North Korea cooperated on defense, including on the development and production of ballistic missiles [PDF]. North Korean scientists also benefited from academic exchanges with Soviet and Chinese counterparts. Though the exchanges may not have been explicitly tied to weapons development, the information learned from research sharing and visits to nuclear facilities could have been applied to a militarized nuclear program, according to Joseph S. Bermudez Jr., an analyst of North Korean defense and intelligence affairs.
Pakistan also emerged as an important military collaborator with North Korea in the 1970s. Bilateral nuclear assistance began when scientists from the two countries were both in Iran working on ballistic missiles during the Iran-Iraq War (1980–1988). In the 1990s, North Korea acquired access to Pakistani centrifuge technology and designs from scientist Abdul Qadeer Khan, who had directed the militarization of Pakistan’s nuclear program. Pyongyang also received designs for a uranium warhead that Pakistan had likely obtained from China. In exchange, Pakistan received North Korean missile technology. It remains unclear whether Khan acted directly or indirectly on the behalf of the Pakistani government. (Khan’s multinational network also illicitly sold nuclear technology and material to buyers, including Iran and Libya.) The nuclear know-how gained from Pakistan likely enabled North Korea to operate centrifuges and thereby pursue a uranium route to the bomb.
Third parties have also facilitated Pyongyang’s program through the illicit shipment of metal components needed for centrifuge construction and nuclear weaponization. North Korea has developed covert networks for the procurement of technology, materials, and designs to boost its conventional and nuclear weapons programs since the 1960s. These networks, once primarily in Europe, have shifted to Asia and Africa, and goods are often traded multiple times before reaching North Korean hands, says Bermudez.
What punitive steps has North Korea faced?
North Korea’s withdrawal from the Nuclear Nonproliferation Treaty (NPT) in 2003 and its missile tests and first nuclear test in 2006 prompted the UN Security Council to unanimously adopt resolutions that condemned North Korea’s actions and imposed sanctions against the country. The Security Council has steadily ratcheted up sanctions through subsequent resolutions in the hopes of changing Pyongyang’s behavior. These additional measures ban arms sales to North Korea, as well as any financial assistance and the sale of materials and technology that could be used for ballistic missiles or nuclear weapons. The measures also impose restrictions on select luxury goods and other foreign trade, as well as inspections of cargo bound for North Korea. Though sanctions have curtailed North Korea’s access to materials, it is difficult to regulate all international cargo deliveries.
Separately, North Korea has a record of missile sales and nuclear technology sharing with countries including Egypt, Iran, Libya, Myanmar, Syria, the United Arab Emirates, Vietnam, and Yemen. It has secretly transferred “nuclear-related and ballistic-missile-related equipment, know-how, and technology,” the United Nations has reported. Given North Korea’s economic constraints, fears abound that North Korea could resort to selling more nuclear material and knowledge, thereby enhancing the potential for nuclear terrorism.
Does North Korea possess other weapons of mass destruction?
North Korea is believed to have an arsenal of chemical weapons, including sulfur mustard, chlorine, phosgene, sarin, and VX nerve agents. The regime reportedly has the “capability to produce [PDF] nerve, blister, blood, and choking agents” and is estimated to have stockpiled [PDF] between 2,500 and 5,000 tons of chemical weapons. These toxins can be fired using a variety of conventional shells, rockets, aircraft, and missiles. The army also manufactures its own protective suits and detection systems for chemical warfare.
North Korea is also believed to possess some biological weapons capabilities, although it became party in 1987 to the Biological Weapons Convention, a treaty banning the production, development, stockpiling, and attempts to acquire biological weapons. In 1988, it acceded to the Geneva Protocol, which prohibits the use of asphyxiating, poisonous, and other gases in warfare. North Korea allegedly has the ability to produce [PDF] pathogens including anthrax, smallpox, and pest (plague), although its ability to weaponize them is unclear.
What are North Korea’s conventional military capabilities?
North Korea’s military is the world’s fourth largest, with nearly 1.3 million active personnel, accounting for about 5 percent of the total population. More than six hundred thousand others serve as reserve soldiers. Article 86 of the North Korean constitution [PDF] states, “National defense is the supreme duty and honor of citizens,” and it requires all citizens to serve in the military.
The regime spent an average of $3.6 billion annually on the military from 2007 to 2017, according to the U.S. State Department. North Korea’s neighbors and adversaries outspend it in dollar-to-dollar comparisons, and defense experts say it operates with aging equipment and technology. Yet, the regime’s forward-deployed military position and missiles aimed at Seoul ensure that Pyongyang’s conventional capabilities remain a constant threat to its southern neighbor.
North Korea has deployed munitions near and along its border with South Korea and also has conventional missiles aimed at its neighbor and Japan in a bid to deter potential attacks. According to a 2021 report by the International Institute for Strategic Studies, a United Kingdom–based think tank, the North Korean military has approximately 550 combat-capable aircraft, 290 helicopters, 400 combatant vessels, 280 amphibious vessels, 70 submarines, 4,000 tanks, 2,500 armored vehicles, and 5,500 multiple-rocket launchers.
Does it pose a cybersecurity threat?
North Korea’s cyberwarfare capabilities have advanced significantly over the years, and its hackers use increasingly sophisticated tools to target government, media, financial, and private institutions around the world. Some experts say that North Korea’s cyberwarfare capabilities now pose a more immediate threat than its military programs.
Pyongyang has invested significant labor and capital into developing its cyberattack capacity. It relied on Chinese and Soviet assistance in the 1980s and 1990s, and today, its hackers train at elite North Korean technology schools and attend top science and engineering schools in China to gain access to advanced technology unavailable in North Korea.
North Korea has demonstrated the ability to devastate critical infrastructure systems and infiltrate military, government, and intelligence networks. Cyberattacks on South Korean banks and media outlets, as well as the 2014 Sony Pictures hack, have been traced back to groups with ties to North Korea. In December 2016, South Korea accused North Korea of breaching its military’s cyber command. In 2017, the Wannacry 2.0 ransomware attack compromised aviation, railway, and health-care networks in the United States, Asia, and Europe. The U.S. Department of Justice charged a North Korean man believed to be a member of the Lazarus Group—which is suspected of being backed by North Korea and responsible for Wannacry and several other high-profile attacks—for his involvement in those incidents. Individuals, think tanks, and government agencies working in national security and foreign policy in the United States, Japan, and South Korea continue to be targeted by the North Korean cyber unit known as Kimsuky.
Pyongyang’s cyber apparatus also increasingly focuses on cybertheft as a major source of revenue for the regime and its weapons program, stealing money from financial organizations and cryptocurrency exchanges. North Korean actors targeted organizations in more than thirty countries for cryptocurrency theft in 2020, and a UN report found that North Korea had stolen more than $2 billion through cybercrime as of 2019.
What drives North Korea’s militarization?
North Korea’s guiding philosophical principles have been juche (self-reliance) and songun (military-first politics). The military plays a central role in political affairs and its position has been steadily elevated through the Kim dynasty. North Korean leadership believes that hostile external forces, including South Korea and the United States, could mount an attack. As a result, in Pyongyang’s eyes, the only way to guarantee national survival is to develop asymmetric military capabilities to thwart its perceived threats.
In the decades since the Korean War armistice, the regime in Pyongyang has grown increasingly isolated, in large part due to its ongoing nuclear pursuits and other military provocations. The North’s economy and impoverished population of twenty-five million are more and more cut off from the global economy, with limited means to acquire much-needed hard currency. Despite Pyongyang’s reputation as a pariah state, Kim Jong-un remains committed to a national strategy of building up the economy and nuclear capabilities jointly.
Because Kim has struggled to deliver on his economic promises, he seeks to consolidate his rule by demonstrating unquestioned military might. The nuclear program thus has a dual purpose: to deter external threats and to bolster the image of Kim.
Since Kim Jong-un assumed power, the country has shed the ambiguous language surrounding its nuclear and missile development, instead vowing to conduct tests whenever it sees fit. Punitive measures taken against Pyongyang seem to have only emboldened Kim’s commitment to strengthening the military. And although diplomatic engagement has in the past temporarily slowed North Korea’s rate of testing, it has not resulted in denuclearization.
CFR’s Scott A. Snyder assesses how Kim Jong-un advanced North Korea’s military during his first decade in power.
In Foreign Affairs, the Center for Strategic and International Studies’ Sue Mi Terry outlines how North Korea succeeded at producing nuclear weapons and why it will not relinquish them.
Reuters presents North Korea’s military advances and nuclear program in these graphics and visuals.
The Heritage Foundation’s Bruce Klingner evaluates North Korea’s cyber threat in this 2021 report.
The James Martin Center for Nonproliferation Studies tracks North Korean missile tests in this interactive database.
The RAND Corporation discusses how the United States and South Korea should counter the risks of North Korea’s nuclear weapons.
Nathanael Cheng, Lindsay Maizland, Amber Duan, and Eleanor Albert contributed to this Backgrounder. Will Merrow created the graphics.
Correction: A previous version of this report erroneously stated that North Korea had six million reserve soldiers. There are six hundred thousand reserve forces. This error was corrected on October 13, 2020.