A surprising, page-turning account of how the wars of the future are already being fought today. The United States military currently views cyberspace as the "fifth domain" of warfare-alongside land, sea, air, and space-and the Department of Defense, National Security Agency, and CIA all field teams of hackers who can-and do-launch computer virus strikes against enemy targets. In fact, as @War shows, US hackers were crucial to our victory in Iraq. Shane Harris delves into the front lines of America's new cyberwar. As recent revelations have shown, government agencies are joining with tech giants like Google and Facebook to collect vast amounts of information. The military has also formed a new alliance with tech and finance companies to patrol cyberspace, and Harris offers a deeper glimpse into this partnership than we have ever seen before. Finally, Harris explains what the new cybersecurity regime means for all of us who spend our daily lives bound to the Internet-and are vulnerable to its dangers.