Hacking the lights out. Computer viruses have taken out hardened industrial control systems. The electrical power grid may be next.

Every facet of the modern electrical grid is controlled by computers. It is our greatest example of physical infrastructure interlinked with electronics. The Stuxnet virus that infected Iran’s nuclear program showed just how vulnerable machines could be to a well-crafted electronic virus. The grid shares many of the vulnerabilities that Stuxnet exposed; being larger, its vulnerabilities are, if anything, more numerous. Although a sophisticated attack could bring down a large chunk of the U.S. electrical grid, security is being ramped up.