It needs to be launched to a very high level. And it needs to be detonated at a very specific height.
The cone of EMP damage is fairly narrow. The horrifying effects would be in concentric circles. In the middle there would be total impact on electronics. But in the subsequent circles outside the max, your car would stop—but it would start back up.
Anyone trying to knock out a city could probably do that. But knocking out a continent would require about a dozen precisely placed nukes.
The bigger concern is that someone is shooting off nukes.
The horrifying effects would be in concentric circles.
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The first time I have heard that. Very interesting.
And almost obvious if you think in terms of an electromagnetic wave. Based on your description it must be the case that the EMP wave propagates to earth but is absorbered/dissipated/scattered at that point leaving the damage in concentric (and diminishing with distance) rings.
Wow!