Billions Spent on U.S. Defenses Failed to Detect Giant Russian Hack The broad Russian espionage attack on the U.S. government and private companies, underway since spring and detected only a few weeks ago, is among the greatest intelligence failures of modern times. The National Security Agency’s headquarters at Fort Meade, Md., is home to a cyberwar room guiding efforts that cost tens of billions of dollars.Credit…Jim Lo Scalzo/European Pressphoto Agency By David E. Sanger, Nicole Perlroth and Julian E. Barnes   WASHINGTON — Over the past few years, the UnitedRead More