Back in the '70s, I always heard "survive hostile battlefield conditions" and never heard anyone talk about comms survival of a nuclear event, but I wasn't in any interesting conversations, such as in front of funding agencies...
To survive an EMP, electronics needs some fancy circuitry. I've never worked with a bit of equipment that had it. It would therefore have to have been through path redundancy.
It was designed to be robust but it wasn't designed to survive nuclear war. There WERE some networks that were designed to survive, though, so maybe some have confused them. I think what I hear seems to confuse MILNET with MILSTAR where MILNET was the military portion of the Internet (what has eventually evolved into NIPRNet) and MILSTAR which is a satellite network designed to be nuclear survivable. When it absolutely positively has to get there.