“I’m pretty sure an EMP attack on the US would trigger full nuclear retaliation just as if they hit us with a traditional nuke, so it seems like a very foolish strategy.”
“an EMP attack carried out the right way would kill about 90% of Americans within a year”
Survivalist wishful thinking. There would be a bit of chaos for a few weeks and then things would start going back to normal, because while the survivalists are hiding in their bunkers, other people would be out fixing the infrastructure to get society running again.
You couldn’t be sure to contain the effects to just the US! Mexico, Canada, and Central America could well also be affected including the Panama Canal. Also the effects are not going to be uniform but spotty...worse in some areas and not much in other areas.
To get a broader effect you’d have to explode multiple devices due to the curvature of the Earth...then again by doing so you might just take out the electronics of nations you didn’t intend....and those surviving nations would see the offending nation as such a threat they may unite to annihilate the offending nation just to keep such an event from happening to them!
Also as the magnetosphere and related magnetic fields are thinned out over the day side and pushed around so that they are thickest on the night side due to solar wind particles...the emp’s would have to be exploded at night at just the right time place and distance to get the maximum desired effects from the magnetic fields. Localized thunderstorms occurring may actually provide some shielding in some areas due to their own strong localized electrical/magnetic activities. Local TV and Radio Towers might provide some protection for surrounding communities due to grounding...Metal content in surrounding mountain ranges and Geological formations may hinder effects.... Cities due to multiple high rise buildings may experience sporadic damage to their electronics...some cars and other transport systems may experience no damage...electrical grid damage may be wide spread but may local systems may stay intact...
I don’t see that our nation would be totally wiped out but we will be stung enough to become seriously pissed off!
In short the EMP’s might be very bad but not total nation killers as we fear...I’d fear a CME from the sun having been launched directly at us quite a bit more! Also the nations that try this have to realize that they may take out other nations’ electronics that they didn’t intend on doing, nations that may very well rise up to destroy the offending nation out of a sense of self preservation!