The main limitation of North Korea’s nuclear program is the unproven state of the re-entry technology of its growing arsenal of long-range missiles. Making sensitive components such as the guidance systems of an ICBM survivable as the missile returns from space to the Earth’s atmosphere is extremely difficult. The North has yet to demonstrate re-entry capability in any of its missile tests, and the way the U.S. talks about the state of the North’s program suggests Washington believes the North isn’t quite there yet. It’s possible that it is and just isn’t showing it, but let’s assume that Pyongyang is still in the exceedingly dangerous window between developing a nuclear weapon and not yet being able to deliver it with any degree of confidence.

If the North finds itself under attack by the United States and determines that it will soon be denied the chance to master re-entry technology, attempting a high-altitude EMP attack may be one of its few remaining cards left to play. This is because a high-altitude EMP attack does not require sophisticated re-entry or guidance technologies. The device is detonated above the atmosphere, after all. In this way, EMP can serve as a sort of bridge between the North’s status as nuclear aspirant and full nuclear power.

My dad was in Honolulu for Starfish Prime. He said the sky turned the color of green jello. Of the three satellites that were lost immediately, two were being tracked by him for the Air Force. Thus did his idyll on Hawaii end as he was reassigned to Thule, Greenland.

He told that story often when I was growing up. Emphasized by him was the assertion that EMP effects were bullshit; what took out his birds was radiation that orbited the earth of its own accord (for five years or more). While some lights went out in Honolulu, nearly all lights did not. Meanwhile, nothing went dark on Johnson Atoll, directly under the test.

But yeah. You don't have to survive re-entry if you're building an EMP. The Soviets had ICBMs for like two full years before they had warheads to put on them.