April 3, 2025: North Korea has tested a missile launched ElectroMagnetic Pulse or EMP weapon. This took place on April 29th as the conventional missile warhead detonated at 72 kilometers altitude. This is the optimum altitude for a ten kiloton/KT EMP weapon. The missile was launched from a base near the capital Pyongyang and detonated over North Korean territory. North Korea was demonstrating that it had the ability to use an EMP weapon high above the South Korean capital Seoul and disable half the national GDP. Seoul is close to the North Korea border and vulnerable to North Korean rocket and missile attacks. A ten KT EMP weapon would impact all of north and south Korea. Because North Korea has a long history of irrational and self-destructive behavior, use of an EMP is remotely possible.

North Korean use of EMP against the south would incur retaliation from the United States, which has been an ally since 1946. Most major industrialized nations can, and some have, built EMP weapons. The national impact of EMP use is known because of a natural one caused in 1859 when an electrically charged geomagnetic storm from our sun, known as the Carrington Event, disrupted and damaged telegraph equipment throughout Europe and North America. If this EMP had occurred a hundred years later, 1959 societies would have been crippled by the damage done to all manner of electronic equipment in the zone of the EMP. It takes several days for a geomagnetic storm to reach earth. The United States and several other nations manage an early warning system to provide time to prepare for a major EMP hitting earth. Some sensitive equipment could be protected by turning it off and, if possible moving equipment to a shielded area like a cave, basement or safe. There would still be widespread damage, but the undamaged items would make repairs and reconstruction move faster. North Korea has lots of tunnels to place vehicles and other equipment in if they used an EMP nuclear weapon over northern South Korea.

Non-nuclear portable devices are quite common and some have legitimate uses. Criminals and military specialists have developed their own uses for this equipment. Meanwhile the United States, Britain and France, the three Western nations with SSBM nuclear powered submarines carrying ballistic missiles, are working on enhancing the EMP protection on these subs. The SSBMs are immune to EMP attacks while underwater. But when they are back at their base they are on the surface and vulnerable to having most or all of their electronics damaged or made unusable. Land-based ICBM and heavy bomber bases, including the missiles, bombers and supporting aircraft, have 1960’s levels of EMP protection but are vulnerable to modern EMP warheads. Their ground vehicles have no EMP protection. Studies are being made to implement some kind of EMP protection for land based ICBM silos. EMP protection for other military and civilian equipment and facilities is uneven. That means anyone employing EMP devices can cause a lot of damage. Fortunately, a major EMP attack is only possible with the resources of a major industrial nation.

For several decades the U.S. government has been thinking about EMP protection to protect major electrical power plants and industrial facilities from an EMP attack, or even future solar burps like the Carrington Event. The danger is that any nation with a satellite launch capability could put a nuclear weapon in low orbit, about 200-300 kilometers up. Once the nuclear bomb is detonated, it creates an EMP which would destroy most of the unshielded military and civilian electronics within one or two thousand kilometers. For the U.S., that would mean most electronics would be damaged, many to the point where they no longer worked. The economy would stagger to a halt, and it would take months to get back to something resembling normal. In the meantime there would be widespread starvation, less medical care and a lot of general unpleasantness. An unfortunately possible worst case scenario is that all electric power production in the US would cease for years, resulting in 95 percent of Americans dying of thirst, violence and starvation.

There would be nasty side effects to such a high altitude nuclear blast. It would create a temporary belt of intense radiation which would destroy or damage many of the low earth orbit satellites up there. There would be $100 billion, or more, in damage to these satellites, and several years of disrupted communications, GPS and weather prediction service until all the damaged satellites could be replaced.

That kind of collateral damage leads many military and political leaders to believe that no one would use an EMP attack. Then again, what's to prevent Iran or North Korea from setting off an EMP nuke in low orbit, in order to disable everyone's satellites? Sounds like a great extortion opportunity. This is one reason more and more satellites are being hardened to resist the kind of radiation surge high altitude EMP would produce. But most of the satellites in low orbit are not hardened, and even those that are protected are not invulnerable to EMP, just less vulnerable.

Many military electronics systems have been hardened by adding shielding against the EMP, which increases the cost of the electronics 10-20 percent, but that is only against 1960’s level EMP. This has been going on for decades, as during the Cold War troops were trained to keep going after the nukes began falling. But there has been no government incentive to harden consumer or industrial electronics. That's where a proposed $5 billion government program to subsidize them for EMP hardening comes in. It's to pay for hardening key items that would make recovery from an EMP attack much quicker and less devastating in the first place. Assuming a lot of other things are done too.

Since some military electronics, notably America’s seven Trident ballistic missile submarines always at sea, would survive an EMP attack, retaliation with an EMP attack, or just nuclear weapons for the sake of pure destruction would take place. Another disincentive for anyone thinking of using the strategic EMP weapon.

Manufacturers of American military equipment have also resumed installing EMP protection on some of their products. AM General, the American developer and manufacturer of the HMMWV hum-V” or hummer military vehicle, has produced over 300,000 of these now iconic military vehicles since the early 198os and sees a lot of future sales disappearing with the introduction of the new Joint Light Tactical Vehicle or JLTV. Yet the American military and many foreign users will continue buying new hummers and to encourage that the manufacturer is pointing out some obvious, and not-so-obvious, advantages of the hummer. For one thing it is still useful and many foreign users note that it is easier to maintain than many post-1980s vehicles which contain much more electronics and tech in general. As many older automobile users have discovered, the presence of all that electronics makes it more difficult for nations with poor infrastructure to repair them. The reason is simple; the hummer is old school in its dependence on electronics and anyone with mechanical skills can repair it. Post-1980s vehicles require electronic diagnostic equipment to find problems and access to electronic replacement parts to make some essential repairs.

AM General recently claimed that EMP-hardened hummers, unlike modern vehicles like JLTV, are not vulnerable to EMP or hacking of any sort. While EMP will disable electronic additions to the hummer, a hardened version of the basic vehicle will continue to operate minus the added electronic features after being subjected to EMP. In addition AM General is continuing to add new features to the basic hummer, but nothing that would be vulnerable to EMP or hacking. AM General used to produce hummers for the Air Force which were EMP hardened to 1960’s levels, such as fuel and bomb trucks, but ceased doing so about twenty years ago.

Meanwhile the fear of enemies using EMP weapons to destroy electronics has many military organizations seeking ways to minimize the threat. Since the 1950s it was known that the EMP put out by nuclear weapons could damage or destroy solid state transistors and microelectronics devices. Back then most military electronics used vacuum tubes, which were invulnerable to EMP. In the 1980s the Russians were found to be using vacuum tube tech, although miniaturized and more reliable, in some critical military electronics systems. Even United States Air Force B-52’s used tube electronics during the 1980’s, with the tubes produced by Poland, a Soviet ally.

Meanwhile you no longer have to use a nuclear weapon to generate a militarily useful EMP. Since the 1990s, devices using High-Powered Microwave or HPM devices have been developed to create focused EMP on demand without all the nuclear blast and radioactivity. The most commonly mentioned device for this is the Active Electronically Scanned Array or AESA radars that are becoming standard equipment in modern warplanes. AESA is more reliable and, increasingly, no more expensive than the older mechanical radar antennas, with a small dish that moved around inside a dome on top of the aircraft. AESA is also easier and cheaper to maintain, which makes a more expensive AESA cheaper, over its lifetime, than a cheaper to buy mechanically scanned radar. More and more nations including China and Russia are manufacturing AESA radars and equipping their ships and aircraft with this stuff.

All these nations are also manufacturing or developing EMP bombs that could be used to sabotage military bases or civilian facilities. For a long time EMP was believed to be an unlikely threat because you needed a nuclear war to create it. Naturally the blast and radiation damage from the nukes was seen as more of a threat than EMP. But now that has changed. You can harden military electronics to resist but apparently not eliminate the threat of EMP damage. Even the JLTV manufacturer, which uses hardened electronics in its vehicle, admits that this is no guarantee most JLTVs will survive EMP attack. The hummer manufacturer's claims about their vehicle being EMP proof is generally acknowledged although no definitive test results have been released and probably never will be. But it is known that older, pre-essential electronics, vehicles are more resistant and some hardening of essential electrical items like the electric ignition system would create the most EMP resistant vehicle available.