EMP Threat Hype
By TorchStone VP, Scott Stewart
We are currently in a time of heightened geopolitical tension along several distinct axes: the U.S. and Iran; the U.S. and North Korea; the U.S. and China; the Ukraine war; the Israel/Hamas war—all while the Kremlin is warning about the possibility of a nuclear exchange as the result of a potential Russia/NATO war. As is normal during times of heightened geopolitical tensions, we are seeing people sharing alarming items on social media pertaining to the threat of an electromagnetic pulse (EMP) attack.
Unfortunately, like the warnings circulated during past times of tension over the past couple of decades, the recent EMP warnings tend to over-hype the manmade EMP threat while ignoring the very real and persistent threat posed by natural EMP events. Balance is needed if one is going to develop a solid understanding of this threat.
Natural EMPs
Electromagnetic pulses, whether they occur due to natural phenomena or are caused by a man-made source, can indeed cause severe damage to communications lines, the electrical grid, and electronic devices.
Naturally occurring EMPs are called geomagnetic storms or geomagnetic disturbances (GMDs) and are produced by solar storms. GMDs can interfere with broadcast media, satellite communications, and GPS systems. The largest-ever GMD, the so-called “Carrington Event,” occurred in 1859, and was named for the British astronomer who first noticed the unusually strong solar storm. The Carrington Event GMD caused an interruption of telegraph service throughout North America and Europe and even damaged telegraph lines and systems in some areas.
GMDs have also damaged electrical grids on several occasions. The strongest GMD, since modern measurements began, caused the shutdown of Quebec’s electrical grid for nine hours in 1989. Solar storms were also to blame for widespread blackouts in 1972 that affected large portions of the United States and Canada. The 1972 GMD even exploded American naval mines that were located deep in the sea. A significant GMD also crippled the electrical grid in Malmo, Sweden, in 2003.
Manmade EMPs
Electromagnetic pulses from man-made sources, such as a nuclear detonation in the atmosphere, are known as High-Altitude Electromagnetic Pulse (HEMP). The phenomenon of HEMP was first discovered in 1962 when the United States detonated a 1.4-megaton device 250 miles above Johnston Island during a test named “Starfish Prime” in the South Pacific. Starfish Prime produced an EMP that accidentally damaged electrical and electronic systems as far away as Hawaii, which was some 900 miles away.
There is very little historical data available on the effects of HEMP because the United States and the Soviet Union conducted fewer than 20 nuclear tests in the atmosphere before the nuclear test ban treaty went into effect in 1963. As a result, most HEMP standards today are based on computer models using data from only a few tests.
There is little doubt that the impact of a HEMP attack could be significant, but the precise amount of damage a HEMP would cause remains uncertain. Thus, any actor plotting a HEMP attack would still be dealing with significant unknowns, including the ideal altitude at which to detonate their specific device based on its design and yield to maximize its effect, as well as the nature of those effects and just how widely they could reach.
Mitigating Factors
When assessing the threat posed by a HEMP to the U.S. mainland, the principle of mutually assured destruction, which has helped deter nuclear war since the USSR became a nuclear power in 1949, would still apply to a HEMP attack. Any nuclear weapons launched against the U.S. mainland—including a HEMP—would result in nuclear retaliation. The American nuclear triad was specifically designed to survive a nuclear attack, so it is highly unlikely that a HEMP attack could successfully disarm the United States ensuring that any country launching a HEMP attack would be certain to face retaliation.
Some people have posited that rogue regimes such as North Korea or Iran are “crazy” enough to attempt a HEMP attack against the U.S., but I don’t believe either regime is that suicidal. Any nuclear weapon launched at the U.S. —whether intended to detonate on the ground or in the atmosphere—would be met with nuclear retaliation. When combined with the immense potential for error associated with a HEMP attack, it makes a HEMP attack highly unlikely. Besides, even a failed HEMP attack is certain to draw a nuclear response, and the only thing worse than having your country destroyed by a U.S. retaliatory nuclear strike for a successful HEMP attack is having it destroyed for a failed attack.
Other commentators have also stated that a nuclear power could provide a weapon to a terrorist actor to use in a non-attributable terrorist attack. Nuclear powers, especially the newer ones such as Iran and North Korea consider their nuclear weapons to be their crown jewels. I simply don’t believe that any nuclear power would ever be willing to give one of their most precious possessions to a terrorist actor—especially when they would not have any way to control how the group would employ the device. The U.S. government would also make great efforts to trace the device back to the nuclear program that produced it and would certainly take retaliatory action against the producer.
Even if a terrorist group was somehow able to obtain a nuclear weapon, they would still face the difficult task of pairing it with a missile and then launching it hundreds of miles into the atmosphere over the center of the United States without being discovered. If a group such as al Qaeda or the Islamic State were to somehow obtain a nuclear device, they would seek to detonate it in the middle of a large city to create a mass casualty attack rather than launch it into space in an effort to fry electronic devices.
The bottom line is that there is a much greater chance the United States will be hit by a natural EMP incident rather than a HEMP attack. According to the EMP Commission, NASA estimates that there is about a 12 percent chance of a significant solar storm occurring in any given decade.
Given this possibility, along with the remote chance that the United States could somehow become involved in a nuclear war, measures to understand EMPs and to harden the electrical grid and other critical infrastructure against them are both necessary and prudent. However, there is no need to over-hype the EMP threat and cause panic every time there is an increase in geopolitical tension.