A US cyberattack on North Korea failed because North Korea has basically no Internet

Five years ago, the United States tried to sabotage North Korea's nuclear weapons program with a computer virus. The campaign relied on a variant of Stuxnet -- malware that disabled Iranian centrifuges, which was a joint project of the United States and Israel. The idea was to use a version of the virus that would be activated when it encountered Korean-language settings. But the campaign faltered -- it was "stymied", by North Korea's "utter secrecy, as well as the extreme isolation of its communications systems."

It turns out barely having an Internet infrastructure is a really good way to avoid the kind of "cyber-Pearl Harbor" US officials have been warning about for years. This isn't exactly a new idea: "North Korea’s hermit infrastructure creates a cyber-terrain that deters reconnaissance," an HP Security briefing from 2013 noted. "Today North Korea’s air-gapped networks and prioritization of resources for military use provide both a secure and structured base of operations for cyber operations and a secure means of communications." And while North Korea's defense gets a boost from its set-up, it also appears to value having offensive cyber capabilities.