“Although Silicon Valley has sold equipment to the N.S.A. and other intelligence agencies for a generation, the interests of the two began to converge in new ways in the last few years as advances in computer storage technology drastically reduced the costs of storing enormous amounts of data. The sums the N.S.A. spends in Silicon Valley are classified, as is the agency’s total budget, which independent analysts say is $8 billion to $10 billion a year. Current and former industry officials say the companies sometimes secretly put together teams of in-house experts to find ways to cooperate more completely with the N.S.A.”
