EMPs are a fantasy. Absolutely and unreservedly a complete fantasy. ZERO have ever been tested, and there’s literally a better use for a nuclear warhead. Not only is it a a completely hypothetical attack, it would look identical to a normal nuclear ICBM attack, and absolutely would result in a traditional retaliatory attack. Why would anyone trade an EMP for all their cities? Literally doesn’t make sense. No one in the nuclear arms control world takes it seriously. It’s a boogeyman for defense contractors and grifters, but I repeat myself.
All that said, GPS denial is a very real thing, and has been repeatedly demonstrated in an operational context. It’s relatively trivial to do. You just need a regular ground based antenna, and not a particular strong transmitter because satellite signals are weak. Just broadcast a different timing signal and voilà! You now tricked someone into thinking they’re 50 miles away from where they really are.
All that said, GPS denial is a very real thing, and has been repeatedly demonstrated in an operational context. It’s relatively trivial to do. You just need a regular ground based antenna, and not a particular strong transmitter because satellite signals are weak. Just broadcast a different timing signal and voilà! You now tricked someone into thinking they’re 50 miles away from where they really are.
https://medium.com/war-is-boring/the-overrated-threat-from-e...
https://www.c4isrnet.com/opinion/2022/07/22/why-isnt-russia-...