Predicting or worrying about disasters is a popular pastime in the Scientific community
Solar storms and nuclear weapons can create electromagnetic pulses can destroy satellites, disrupt GPS and make parts of infrastructure fail. EMP's cam be man made too, created by weapons discharge.
This is a real threat, discovered the hard way in 1962, when a Pacific nuclear test caused electrical damage 870 miles away in Hawaii
The Earth has a vast natural magnetic field, courtesy of currents inside its iron core and over millennia it gradually changes.
As long as it is stable it is not noticeable except for turning compass needles.
But what if something forced it to move? The change would produce currents in long conductors such as power lines or telecoms cables.
The field is weak, but a shift across miles of cable can induce powerful currents, strong enough to burn out fuses or damage transformers and other electronics.
A nuclear explosion - can produce currents that disrupt smaller devices. In fact, microchips are easily burned out by a few volts in the wrong place.
Do we need to worry about naturally occurring geomagnetic storms, caused by the solar wind interacting with the Earth's magnetic field? Not really, we need to plan with robust, protec6ted infrastructure..
Should we worry about Man produced electromagnetic pulses (EMPs) by nuclear weapons, or so-called e-weapons, devices that have been developed to disrupt enemy electronics?
If something causes widespread and persistent black-outs and equipment damage the economic damage – and human problems – would be enormous.
But then again thinking about it, if some lunatic set of a nuclear device or similar. would you really be thinking that the prime cause of the damage to the economy or the loss of human life.