(On Cable TV, July 2017) Documentarian Alex Gibney is almost a national treasure at this point, able to transform complex modern topics in hard-hitting yet compulsively viewable documentaries. In Zero Days, he takes on one of the most fascinating computer security issues of the century so far, which is to say the Stuxnet worm that, in 2005, spread over the planet yet appeared to very specifically target uranium centrifuges used in the Iranian nuclear weapon development program. Throughout it duration, Zero Days patiently describes the way the worm was discovered, its complex peculiarities, what was hidden in the code, and why, piece by piece, security experts identified the United States and/or Israel secret services as likely candidates for the worm’s development. But as Gibney can’t get any official confirmation, he gets mad and, midway through, brings out his own confidential sources: Intelligence Community officers who, concerned with the potential of cyber-weapons, are willing to confirm and explain what had, up to this point, been merely informed speculation: NSA and Israel developed Stuxnet, then Israel made it more virulent and allowed it to escape with little thought about detection. (It probably also ran the more aggressive Stuxnet alongside a more conventional campaign of targeted assassination of Iranian nuclear experts.) Much of this story is familiar to people even remotely knowledgeable about cyber-security (check out Stuxnet’s Wikipedia page for details) but then Zero Days has a final revelation of its own: Nitro Zeus, a set of exploits and plans designed to bring down Iran’s infrastructure. It’s that kind of capability that led the NSA officers to leak details of US operations. It’s also that kind of stuff that should keep you awake, especially now that more leaks have suggested the existence of a Nitro Zeus aimed at Russia … and Russia’s own infrastructure-meddling experiments in Ukraine. Twenty-first-century warfare is not going to be about tanks and missiles, and it’s going to reach people in their own homes. Zero Days is a good primer on how bad it can be. By the time it replays the Obama administration’s happy announcement of a deal regarding the end of Iran’s nuclear program, the implied meaning is far more sinister: The US won its first cyber-war. But there will be others.