HR668, deemed the 'Shield Act', is an attempt to address the insane vulnerability of the US electrical grid to a host of threats. Like similar acts before it, it represents a profound sanity and a focus on some of the few things that governments actually can be good at. Also like similar acts, it will likely go nowhere. It's almost like we have a death wish as a civilization.
The brute truth is that a close cousin of the 'Army of the Twelve Monkeys'---call it the 'Army of the Twenty-Four Angry Smart Rednecks', is all that it would take to end civilization as we know it in the US. The article talks about things like terrorist EMPs, low kiloton nuclear weapons at extremely high altitude, and intense solar events like the Carrington event.
All of these are real and quite legitimate threats. But the fact of the matter is that even something far simpler would be just as devastating, perhaps even moreso.
Back when the 'great and the good' decided that we had to meddle in the Balkans back in the late 90s, I worried quite a bit about this scenario. You see, Serbs, for instance, don't stand out in the US. Most of them are Orthodox or Catholic. One is a friend of mine for some years at work, and few people would guess that he was a foreigner. It is PROFOUNDLY DANGEROUS in a country with infrastructure as fragile as that of the US to mess with countries having a population that would not draw much attention in the US and fairly high levels of intelligence and technical acumen.
There's a good chance we'll get some hardcore solar storms out of the upcoming solar maximum this year or early next. It's also true that 24 angry smart rednecks (which can be translated into any language you choose as long as it produces that population segment) could trash our power grid beyond repair. Ultra high voltage transformers are pretty much absolutely essential to maintaining said grid, very vulnerable, fairly small in number, have negligible spares available, are not produced in the US, and have very long lead times for new orders.
A sane government would stockpile spares in safe distributed locations. We don't have a sane government.
Judging by the difficulties in restoring power after the Derecho storms, the institutional competence of the power companies and Corps of Engineers appears to be slumping also.