In a hypothetical nuclear war, did any of the major nuclear powers intend on detonating some of their warheads at high altitudes in order to damage their enemies' electric infrastructure with an electromagnetic pulse?
If its US v USSR then yes, they have so many warheads some of them almost certainly would be for launched for EMP to disrupt communications. Everyone else only has the warheads to go city busting ( forget the military target only talk , unless you have enough to do a first strike and are sure of taking out the oppositions ability to hit back, in a major exchange it would be inflict as much pain as possible )
The Day After, Threads, and (somewhat more reliably) at least one RAND study that I read includes the usage of high-altitude nuclear detonations to create EMPs in a US - USSR exchange scenario. The last especially seems to indicate that the idea of creating EMPs factored in NATO thinking by the 1980s.
They'd be a good opener for a bolt from the blue, assuming either the US or the USSR violated the restrictions on nukes in orbit. Sure, military systems are hardened, but considering there's only half an hour tops before the missiles land it doesn't take much confusion from stop lights not working to cause a significant delay.