EMPs, or electromagnetic pulses, are intense bursts of electromagnetic energy that can be utilized to damage electronics. Man-made nuclear EMPS are impressive weapons of war that are sparingly used due to their highly destructive nature.
There are natural EMPs that can be caused in small form due to lightning or in large form due to geomagnetic storms. Man-made EMPs are generally created through nuclear explosions.
Essentially, these weapons emit a pulse that damages or destroys the electronic systems in an object due to damaging current and voltage surges.
History of man-made EMPs
Man-made EMP capabilities were first discovered as the world's superpowers started nuclear tests. Notably, the Starfish Prime test in 1962, where a 1.4 megaton bomb was detonated above the Pacific, resulted in damage to electrical equipment more than 1,400 kilometers away.
During the height of the Cold War, EMPs were investigated as weapons of mass destruction quite extensively by the US and the USSR. During this investigation, multiple low earth orbit satellites failed, which caused both countries to realize just how damaging the weapon they had stumbled upon was.
In warfare, the use of a nuclear EMP weapon is regarded in the same realm as nuclear attacks. They have the potential of destroying an entire region's electronics, which, in the modern information age, would practically be the end of life as we know it.
Aside from nuclear EMPs, military engineers and researchers have been exploring ways to create non-nuclear EMPs essentially since the birth of nuclear EMPs. Non-nuclear EMPs are now a reality for militaries around the world, but these weapons are much more localized than their nuclear counterparts.
Non-nuclear electromagnetic pulses
Focusing in on NNEMPs, these weapons are much less powerful, ranging from hundreds of meters of effectiveness up to several kilometers. These much more targeted ranges and effects make NNEMPs highly effective non-life-threatening military weapons. In other words, they can do significant damage to a localized region without affecting structures or human life.
The way that NNEMPs are traditionally delivered to a target is rather unique, though. It's not through a vehicle carrying a NNEMP device, but rather there are NNEMP missiles and bombs that are mounted to aircraft and drones. For example, Boeing has built and effectively tested the CHAMP missile.
NNEMP technology is also not a highly complex one, which means that countries of varying sizes, capabilities, and military prowess have the technology in their arsenal. When NNEMPs are implemented in bombs or missiles, they are referred to as e-bombs. Notably, the US used an e-bomb in 2003 in an effort to knock out Saddam Hussein's propaganda network.
Practical military uses of EMP technology
Due to their non-physically destructive nature, NNEMPs can be used against a variety of targets, depending upon their intended effect. Society and military structure are built heavily upon the use of electronics, meaning that the effectiveness of EMPs as weapons are essentially endless.
In war-fighting situations, they could knock out naval ships, disable communications networks, jam tanks, kill radar networks – you name it. If it's electronically based, it can probably be knocked offline by an EMP device.
While all of that may sound a little scary, militaries, and even you have the ability to protect against EMP attacks, though due to the restrictivity of the protection, it's not widely used unless absolutely necessary.
Covering electronics in a faraday caging material keeps the electromagnetic pulses from overloading the circuitry in the systems. Faraday cages are the most effective means of protection for electronics, but unfortunately, they also keep signals from exiting the cage, not just entering. This means that while you could protect a connected device from an EMP attack using a faraday cage, it would only work on network local to the inside of the faraday caging.
For a more in-depth engineering look into how EMPs function and are generated, take a look at the video below from Engineer Tim Carty.