Some consider North Korea to be the rogue nation most likely to use an electromagnetic pulse (EMP) to attack America; Iran is also seen as quite likely to do it. It matters little which succeeds.

Here is a lengthy 2013 video about an EMP attack, what would happen and why:

The possibilities and consequences of an EMP attack on America are too horrific to contemplate; the “legitimate news media” generally ignore them. We therefore tend to relegate them to the realm of remote “tin foil hat conspiracy theories” and to focus instead on more congenial stuff — the latest sex scandal, Hillary Clinton’s campaign van parking in a disabled-only space and other matters unlikely to impact America to an extent even approaching that of an EMP attack. Meanwhile, most of “our” Congress Critters, who should know better, focus on opinion polls, filling their campaign coffers and getting richer personally while neglecting our atrophying missile defense systems and…