The simplest electro-magnetic pulse or EMP weapons are, put simply, nuclear weapons detonated at high altitude. A high-altitude nuclear blast would overload and destroy electrical circuits and infrastructure, and create blackouts over wide areas for extended periods of time. Imagine your life without the internet, telephone, electricity, or cars — in short, being part of a 21st Century population trying to sustain itself with Colonial Williamsburg technology — and you get the idea. Without the means to recover from that sort of attack quickly, a modern society can’t survive for long.

The Heritage Foundation has published this background paper on the EMP threat, which itself links to this study commissioned by Congress, which examines the threat in more detail. Although I’ve read some of the predictions about the potential consequences of an EMP strike that sound exaggerated, I do think EMP is a danger we should take seriously with respect to our defenses, and also, our capacity to recover our infrastructure after an EMP attack.

Last month, former CIA Director James Woolsey made some members of the House Armed Services Committee nervous when he warned, “There is now an increasing likelihood that rogue nations such as North Korea … will soon match Russia and China in that they will have the primary ingredients for an EMP attack.”

For South Korea, the EMP threat could be particularly dire. The ROK has one of the world’s highest population densities, and its defense is as dependent on technology as the rest of its society. I’m not surprised, then, that the South Korean military is denying that North Korea has EMP weapons … at least for now.

Meanwhile, another writer suggests that our own EMP weapons could help restore our failing military deterrence of North Korea.

One way to threaten preemption even without missiles is to further develop a non-nuclear electromagnetic pulse (EMP) weapon that could neutralize missiles on the launcher. Because North Korea will soon develop road-mobile missiles capable of firing nuclear weapons, the further development of non-nuclear EMP systems capable of taking out, say, a 50-square-kilometer joint fire area, would also shift the cost-benefit calculus against North Korea. [Patrick Cronin, The Diplomat]

There is very little (but some) publicly available information about non-nuclear EMP weapons. According to Global Security, the U.S. military may even have used them against the Iraqi military in 1991.

The use of non-nuclear EMP doesn’t raise the same concerns about nuclear escalation and clouds of radionuclides drifting over, say, China. On the other hand, South Korea is almost certainly far more dependent on technology, and thus far more vulnerable to EMP warfare, than the North. The area south of the DMZ is heavily populated, whereas the area to the North is thinly populated and technologically backward. Whether a first use of EMP is really a good idea depends on unknowable facts, such as the imminence and scale of the threat we’d be preempting, the capability of the weapons, and the likelihood that North Korea could respond in kind.

For a more scaleable form of deterrence, I’m much more comfortable with this idea, myself.

While North and South Korea agreed some years ago to forego psychological warfare against each other, the North is a flagrant purveyor of vitriol and falsehood. Surely the alliance can better saturate the North with uncomfortable facts—from pictures of Kim Jong-Un’s luxury houses side by side with North Korean gulags, to video lectures by North Korean refugees who have managed to escape the world’s most oppressive regime.

In fact, I don’t see any good arguments against doing these things in response to North Korea’s tests of SCUD, 300-millimeter rockets, or ICBM engines. If one of our goals is to slow the rate of North Korea’s progress toward acquiring an effective nuclear arsenal, wouldn’t it make sense to convince Kim Jong Un that that progress also carries risks, and that time isn’t on his side?