AJ Lake wrote:

I'm sure that our (US) military protects for EMP

No it doesn't and never has. The Russian plans for preemptive strikes
included high air bursts over major centres of population to cripple
communications. The Soviets /knew/ that the USA was entirely vulnerable to
EMP, and still is.

Perhaps you know the technology currently used?

Yes. We Brits have military communications equipment to deal with EMP -
it's /all/ valve based. Trying to protect semiconductor gear against EMP
is like trying to protect telephone equipment against lightning - entirely
futile!

Bob