... earth charge seeking opposite sky charge that ALSO happens to be cooking electronics, the strike path & induced surge from the actual strike has a dramatic kill effect for sure but having St Elmo's Fire leaking from any & everything is cooking electronics too even if the main bolt gets drawn fifty of a hund yards away
E-fields strong enough to ionize the air and produce feet of corona streamers trying to connect to a nearby leader are certainly a killer for semiconductors near to, or touching, them. But the moments just after the strike can cause damage by another mechanism, too.
The surge in the miliseconds after the strike doesn't require the strike to be nearby, or even cloud-to-ground. In fact, the ground-currents spreading out from the edge of the cloud's electrical shadow are actually worse than those right under it. So the damage is more widespread.
As the cloud-to-ground field builds up before the strike, charge accumulates below the cloud. Once the cloud gets substantially discharged by a strike, that charge is no longer pulled. It goes away by self-repelling and spreading out - violently. At and beyond the cloud shadow's edge you get ground currents comparable to an actual strike.
The area beneath the cloud is the middle of a dual-capacitor voltage-divider, and the cloud discharges fast enough that the effective frequency is very high. Lightning currents in a conductor will jump through the air rather than take a sharp bend in the conductor, due to the tiny inductance of the bend. Similarly, this high frequency causes skin effect in the ground, keeping this current initially concentrated in the top bit of soil moisture, possibly the very top of the soil which just got moistened by the rain. (Also in reasonably straight metal conductors, of course.) Any interruption of this path - like by a drainage ditch, with wet soil in the banks above the actual water level - and the ground current is likely to throw a bolt across the gap rather than pass under it.
(This is why, just like you don't take shelter from lightning under a tree, you don't take it in a ditch. Come a ground-current surge and YOU're in the path across the ditch with the shortest gap. B-b )
But the large charge discharges slowly enough that there are LOW frequency components that can TAKE bends. So your wires, or plumbing, don't have to be straight to bring current in from acres of "antenna" / "capacitor plate" to hunt for a discharge path through your house and its electric equipment. Well or septic field on one side of a gap, electric or phone feed on the other, and oops! (But in an across-a-gap bolt, the ionization raises the conductivity and the magnetic field creates a "pinch effect", so the current stays in the bolt for a longer time, rather than spreading out.)
My brother (also and electric/electronic techie) tells of a guy he knew in Michigan with a farmhouse, out in a field, at the end of a long drainage ditch. Though his house wasn't hit, practically every time a thunderstorm came near (about every three days in the summer) he'd lose some piece of electronics, from the electrical fun-and-games when the ground currents went through his house rather than across the ditch.
