I’m not that impressed with EMP weapons.
EMPs have been touted as the next big thing since WWII, when they promised that the new weapons would make the enemy bombers just fall out of the sky. While they were able to stop plane engines under controlled test conditions, when they actually tried them out during real battles, the EMPs failed miserably.
In the 1970s, they were touting EMPs as a way to stop fleeing vehicles. Just blast the car with an EMP, its electrical system shorts out, and the car stops. Again, it worked well in controlled test conditions, but not so well in actual field use. But, they were certain that they could work the kinks out and have the system working fairly soon.
Every few years, I hear the same story all over again. They are going to use EMPs to stop cars, and again, they just have a few more kinks to work out and the systems will be reliable. Makes me laugh. They’ve even fielded a few systems like this, but they still aren’t all that good at what they do.
EMPs suffer from the inverse-square law, meaning that the power of the EMP drops off with the square of the distance. Double the distance, and you’ve got 1/4th of the EMPs power level. At 10 times the distance, you’re at 1/100th of the power level.
With current technology, the only way to get an EMP massive enough that it can do some widespread damage is to use a nuke. And let’s face it, if we’re using nukes, we have bigger problems than just our power grid.
Another problem with EMPs is that any kind of metal box tends to shield whatever is inside from the EMP. Electric fields travel around the outside of a metal box, leaving whatever is inside unharmed. An electrical conductor moving through a magnetic field, or a magnetic field moving through an electrical conductor, causes current to flow. So the magnetic portion of the EMP gets dissipated in eddy currents induced into the metal. Car bodies (except for plastic ones), tool boxes, and metal frame construction, and all sorts of things reduce the effectiveness of an EMP.
Yes, a nuke-scale EMP can destroy a lot of stuff in power systems. I’m not going to argue with that one. But it’s not going to be quite the doomsday weapon that some folks make it out to be.
And besides, as has already been pointed out, it’s not like most terrorist groups even have the ability to launch a few dozen EMP-causing nukes over the continental U.S.
When the U.S. military wanted to knock out Iraq’s power systems, they didn’t resort to nukes or any kind of EMP weapons. They used simple metal chaff. And that actually worked very well.
I don’t know why those articles are talking about hardening military equipment from EMPs. That kinds of stuff has been done for years. Ring grounds (literally, a metal ring around the building), halo grounds (again, a ring, but up around the roof instead of down low), Faraday cages, and Ufer grounds (grounding rods encased in the building’s concrete foundation) have all been standard for decades. Nothing new there. Protects you from both EMPs and naturally occurring things like lightning and solar events.