Why wait for the sun to fry our electronic, when a HEMP war could accomplish the same any time we choose?

HEMP: High-altitude ElectroMagnetic Pulse triggered by denotating a nuclear weapon above the atmosphere. 3-5 such explosion would cover the entire US. Global impact would require righly 100 -- a small fraction of the available explosives to all nine nuclear armed states.

I speculate that Trump changed his tune of "Rocket Man" when he was informed of the HEMP impact the NKorean nuke-ICBM arsenal could have even without accuracy and reentry vehicles.