Apparently you have never worked with wifi — ever notice that wifi drops out when you talk on your wireless phone?
No, those EM waves are not visible but they exist. Our eyes are tuned to a very narrow band of the electromagnetic spectrum. The band of frequencies that affect electronics are outside the visible spectrum.
It is the stuff that you can't see that can hurt you or at least the electronics. Actually, the old neutron bomb is a similar device only it ejects particles vs em waves.
There is a whole science dedicated to making electronics less susceptible to the noise sources. Especially for the military.
Interesting: apparently a nuke device frequency band is between 10 to 250MHz which is not super high. However, as the device geometries get smaller and smaller it makes you wonder if modern electronics is less susceptible. However, a tuned device that is specifically designed for EMP effect will take this into account.
Another thing, as frequencies increase, the propagation path through the system is less predictable. That is probably both good and bad. Anyway, high frequency shielding might be easier. Who knows.
“Apparently you have never worked with wifi — ever notice that wifi drops out when you talk on your wireless phone?”
If that’s your basic understanding o frequencies, you don’t know much.
“ever notice that wifi drops out when you talk on your wireless phone”
Mine doesn’t. Why do you have so many problems for being such as “expert”?