A very under-rated threat...

I'm reading a book called 77 Days in September, and it is an eye-opening book.

The premise is that a terrorist enemy (I presume someone like North Korea or a rogue Islamist group bent on destroying the US) launches a 40 kiloton nuclear device 300 miles straight over Kansas, and uses it to generate an EMP effect that cripples the US, Mexico and most of Canada.

The author makes note of a report, last written/updated in 2008 and presented to the Office of the President every year before the SotU Address.  I looked this over and was shocked at just how accurately the author has captured the facts in his work relating to just how unprepared this nation is for such an event.

The effects of an electromagnetic pulse generated by a nuclear detonation have been well known since 1945.  I'm no expert (and the science is tough to read through), but my understanding of the problems associated with the process is that the higher the detonation, the larger the area effected (all line-of-sight) and the larger the detonation's component force, the worse the effects within that area.

The long and short of the issues is this:

37 sovereign nations have the means of producing (or access to) technology that would allow a device of sufficient size to climb more than high enough to shut down America/Canada/Mexico's electrical grids for as long as it would take to replace as much as 50% of all production, distribution and transmission facilities over most of the continent.  Seven nations have the means to produce weapons that are capable of such an attack, and all of those are by no means our "friends"... and (more terrifying, perhaps) not all can adequately account for their nuclear inventories (Russia and Pakistan top that list).

More importantly, we (the US) have no means of preventing this attack once it is initiated.  No adequate, or even functional, missile defense system has been developed that could target a missile launch initiating off the east or west seaboards from as far away as 25 miles and moving almost straight up.  Once launched, the weapon would effect all satellite equipment parked in geosynchronous orbit above the continental US, with either immediate or eventual failure of said equipment as the ultimate result.  All electronic devices, from wrist watches to city-wide electrical and water utility systems, would fail simultaneously.  More than 70% of all vehicles not specifically hardened or sheltered from the effects would cease to function.  All traditional (and now vital) means of communication would fail... cell phones, land lines, radio broadcast facilities, televisions, and the internet would all cease to work.

The crisis doesn't stem so much from the destruction initially felt by the attack, but instead by the fact that repair or replacement of said infrastructure would be a task whose timeline would be measured in decades... not days.  The only aspects of modern technology that have a better-than-average chance of surviving the attack would be those employed by the military... and replacing those items as they are damaged, worn-out or fail will be initially impossible, as well.

In short, the entire USA would be reduced to a nation of people whose entire "world" is reduced to a circle roughly 8 miles across... or the distance one could walk away and back under perfectly normal conditions in one twelve hour period of daylight.

The report linked above is big... but it is worth a glance.  Sobering, to say the least.