As Kim Jong un’s North Korean regime continues to steam toward a nuclear future, a great deal of attention has been paid to the idea of a nuclear strike on U.S. soil.  It makes sense: such a strike would be the most horrific and tragic attack on America in its history, and could potentially result in a greater loss of life than any singular attack ever has before it… but among those in the know, there’s been another, more insidious threat looming on the North Korean horizon: the threat of an EMP attack.

An EMP, or electromagnetic pulse, is a byproduct of a nuclear detonation that overloads electrical circuits.  That means an EMP doesn’t simply result in a power outage, it has the potential to render electronics inert, to destroy infrastructure, and to plunge the United States back into the dark ages.  By many estimates, a single nuclear warhead could do far more damage to the U.S. in the form of an EMP attack than it could with a ground (or near ground) based detonation – so desperate is our society’s reliance on power to function.

North Korean Minister of Foreign Affairs, Ri Yong Ho, who warned that North Korea’s next nuclear test may be over the Pacific, has now expanded upon that threat to include the word “atmospheric.”  Some have questioned the veracity of Ri’s statements, as they haven’t come from Kim himself as so much of North Korea’s bluster often does, but another senior North Korean official confirmed this development with CNN on Wednesday.

“The foreign minister is very well aware of the intentions of our supreme leader, so I think you should take his words literally,” Ri Yong Pil, a senior diplomat in North Korea’s Foreign Ministry, said.

North Korea is well aware of the weaponized potential available to them in the form of electromagnetic pulses, and there’s at least one very good reason for them to shift their strategy toward an EMP centered attack, rather than ground target detonations: the suspected failure of their ICBM warhead reentry vehicles in previous tests.  A detonation intended as a means by which to execute an EMP attack could be done at much higher altitudes, as in dozens, or even hundreds of miles above the earth’s surface.

Here in the United States, we’re no strangers to the electromagnetic pulse produced by a high altitude nuclear detonation.  Technically, we’re the ones that confirmed it through practical application back in 1962 with a project called “Starfish Prime.”

At the time, our intent was to study the effects of radiation at high altitudes, but as the Thor rocket we launched, armed with a W49 thermonuclear warhead, reached its predetermined altitude of nearly two hundred and fifty miles above the earth’s surface and detonated, a microburst of energy surged through electronic instruments, knocking out at least six satellites and bringing power down in parts of Hawaii, nearly a thousand miles away.

To date, Starfish Prime remains the most powerful nuclear detonation ever conducted high up in the earth’s atmosphere, at a sizeable 1.45 megatons.  For a frame of reference, estimates place North Korea’s most powerful dual stage (thermonuclear) warheads at around 120 kilotons.  If we do away with the vernacular associated with units of nuclear measurement, that translates as such: Starfish Prime was the equivalent of around 1,450,000 tons of dynamite, while the best North Korea could currently muster is closer to 120,000 tons.  If you happen to be among the Americans in the effected region after an EMP attack, however, that’s sort of like discussing the difference between taking a .45 caliber round or a 12-gauge slug to the face.  One might be more powerful, but the result is the same.