[News in War History] Power and Communication Blackout Is Not a 'Groundless Fear'... North Korea's Air Explosion Drill Draws Attention to 'EMP Bomb'

Electromagnetic Waves Generated by Nuclear Airbursts
1962 US Nuclear Test Paralyzed Hawaii
EMP Threat Grows as Advanced Devices Increase

Editor's Note[News in War History] is a content series created to provide multifaceted perspectives on the constantly evolving global news of wars and conflicts. Through 'News,' we first examine the current situation; through 'History,' we analyze the hidden meanings behind the news; and through 'Implication,' we offer insights into the near future. We visit you every Sunday, and after 40 episodes, the series will also be published as a book.

North Korea recently announced that it conducted a tactical nuclear warhead airburst firing drill, raising concerns that it might be aiming to acquire the capability to carry out electromagnetic pulse (EMP) attacks using nuclear weapons. EMP is known as a terrifying weapon that uses the powerful electromagnetic waves generated by a nuclear weapon's airburst to simultaneously disable electronic devices in the surrounding area.

Especially if an EMP warhead explodes over a large city filled with various power grids and communication networks, it could temporarily halt the operation of key urban infrastructure, potentially causing a major disaster. Some science fiction (SF) movies depict cities paralyzed by EMP attacks and people plunged into chaos, which has heightened public fear.

On the 28th, North Korea's Korean Central TV announced that the short-range ballistic missile (SRBM) launched the previous day in the Junghwa area of North Hwanghae Province was tested to explode in the air at an altitude of 500 meters.
[Image source=Yonhap News]

Concerns about EMP attacks have been raised not only in South Korea but also in other countries such as the United States, especially after Russia's nuclear threats increased following the Ukraine war. The genre of 'EMP Apocalypse,' where EMP warheads explode worldwide simultaneously and human civilization falls centuries behind, has recently gained popularity against this backdrop.

However, the scientific community points out that the destructive power of EMP warheads is often exaggerated in movies and some media, and there is no need to fall into baseless fear. So, what level of damage would actually occur if an EMP warhead exploded?

◆News: "North Korea Conducts Nuclear Airburst Strike Demonstration"

On the 28th, North Korea's Korean Central TV announced that the short-range ballistic missile (SRBM) launched the previous day in the Junghwa area of North Hwanghae Province was tested to explode in the air at an altitude of 500 meters. Footage of the airburst training released by North Korea.
[Image source=Yonhap News]

Let's first look at the related news. On March 28, North Korea's Korean Central News Agency (KCNA) reported that the North Korean military conducted a nuclear airburst test firing. KCNA stated, "On March 27, the missile unit responsible for important fire strike missions on the central front conducted a demonstration training firing to familiarize subordinate units with the procedures and processes of important fire strike missions," adding, "A military unit's direct training company was mobilized, and two ground-to-ground tactical ballistic missiles were fired in a nuclear airburst strike demonstration."

North Korea revealed that it conducted a drill detonating a tactical nuclear warhead at an altitude of 500 meters, raising concerns that it might be training to acquire 'nuclear EMP (Nuclear Electromagnetic Pulse)' attack capabilities. Nuclear EMP refers to a strategic weapon that detonates a nuclear weapon at an altitude above 30 km to disable telegraph and communication networks in urban areas.

When a nuclear weapon is detonated in the air, it emits a massive amount of radiation, which collides with atmospheric oxygen, nitrogen, and other substances, generating powerful electromagnetic waves. These waves rapidly spread to the ground, damaging semiconductors and circuits inside various electronic devices, which can plunge metropolitan areas into great chaos.

Voice of America (VOA) reported that suspicions have been raised both inside and outside the United States since 2021 that North Korea has succeeded in developing nuclear EMP warheads and possesses some. Some have even claimed that certain communication failures in South Korea since the 2010s were due to North Korea's EMP warhead tests.

◆History 1: 1962 US Pacific Nuclear Test Causes EMP Damage 1,400 km Away in Hawaii

The image of Dr. Arthur Compton, an American nuclear physicist, who appeared as the cover model for Time magazine in January 1936.

So, when was the EMP warhead first developed? The concept of the EMP warhead itself is said to have emerged in the early 1920s, about 100 years ago. The 'Compton Effect,' discovered in 1922 by American nuclear physicist Dr. Arthur Compton, laid the foundation for the birth of the EMP warhead.

According to the Federation of American Scientists (FAS), the Compton Effect discovered by Dr. Compton refers to the phenomenon where electrons are ejected from atoms when radioactive materials such as X-rays or gamma rays collide with other atoms. At the time of discovery, this became a major theory proving the particle nature of light, not just its wavelength, and Dr. Compton was awarded the Nobel Prize in Physics in 1927 for this achievement.

Later, in 1942, during the secret nuclear weapons development project known as the Manhattan Project in World War II, scientists involved warned that a nuclear explosion could generate a massive amount of electromagnetic waves due to the Compton Effect. However, at that time, when vacuum tubes and transistors were just beginning to be used, the number of electronic devices was small, so these electromagnetic waves did not cause immediate problems.

An artificial aurora captured in Honolulu, Hawaii, immediately after the 1962 high-altitude nuclear explosion test by the U.S. military called 'Starfish Prime.' [Image source: U.S. Defense Threat Reduction Agency (DTRA)]

The terrifying power of EMP as a weapon was proven in July 1962 during the US high-altitude nuclear test called 'Starfish Prime.' The US military conducted a high-altitude nuclear test over Johnston Atoll, about 1,450 km from Hawaii. They detonated a 1.4-megaton nuclear warhead at an altitude of about 400 km.

The nuclear test unexpectedly generated a massive electromagnetic pulse. The US military failed to accurately measure the EMP damage, but significant damage occurred in Hawaii, located 1,450 km away. About 300 streetlights simultaneously went out, some telephone lines were disabled, and theft alarms sounded all at once, causing chaos throughout the Hawaiian area.

After realizing how terrifying the power of nuclear EMP was, other nuclear powers at the time, including the UK, France, and the Soviet Union, also began conducting EMP tests and experiments to secure EMP warhead capabilities.

◆History 2: US Military Uses Non-Nuclear EMP in Iraq War... Development Competition

In March 2003, during the Iraq War, U.S. Marines occupying Baghdad are toppling a statue of Saddam Hussein. [Image source=AP·Yonhap News]

From the 1990s, after the Cold War, global nuclear disarmament efforts intensified, limiting the use of nuclear EMP warheads. Consequently, non-nuclear EMP (NN-EMP: Non-Nuclear Electromagnetic Pulse) bombs, which do not contain nuclear material, were developed.

During the 2003 Iraq War, the US military used this non-nuclear EMP weapon in combat, marking the first practical use of an EMP attack. The US military fired a 'High-Power Microwave' warhead that generated over 2 billion watts (W) of electromagnetic waves in a short time to attack Iraqi broadcasting stations. As a result, the targeted Iraqi broadcasting station and all electronic devices within a 1 km radius were completely disabled.

Following this, dramatic depictions of EMP attacks appeared in various movies and media, increasing public fear of EMP warheads. In response, US authorities released a fact sheet in 2003 to counter fake news and excessive fear.

According to the fact sheet released by the Washington State Department of Health, EMP warheads do not directly affect the human body and are weapons that disable electronic devices without causing casualties. It is reported that damage can be significantly reduced by installing appropriate shielding devices on circuits and semiconductors in advance. In the US, shielding devices to minimize EMP damage are already installed in vehicles and major telegraph and communication facilities.

◆Implication: Increasing EMP Risks with Advanced Technology Development

[Image source=Reuters Yonhap News]

In fact, whether nuclear or non-nuclear, the damage caused by EMP increases as advanced technology develops. The use of semiconductors has greatly increased due to various automated devices, artificial intelligence (AI), and autonomous vehicles, and modern society's heavy dependence on power and communication networks makes it much more vulnerable to EMP attacks than in the past.

EMP warheads mainly explode outside the atmosphere, so unlike conventional nuclear attacks, the possibility of radioactive materials harming the human body is low. Most radioactive materials disperse before reaching the ground. Also, the electromagnetic waves occur for a very short time and do not significantly affect the human body.

Moreover, simple devices such as radios or flashlights powered by batteries, or older gasoline or diesel engine vehicles that start manually, are unlikely to suffer major damage. Conversely, electric vehicles with built-in batteries or modern vehicles that heavily rely on electronic systems for starting and operation are likely to suffer significant damage.

Because of this, EMP warheads are even called the most efficient weapons that poor countries can use against wealthy countries. Even if wealthy nations develop non-nuclear EMP warheads for retaliatory attacks, technologically lagging developing countries with fewer electronic devices are less likely to suffer major damage. This issue applies equally to the standoff with North Korea. We sincerely hope that countermeasures against the possibility of EMP attacks will be established as soon as possible.