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.