“One of the two main buildings at the former plant has since housed a sophisticated NSA unit, one that has benefited the most from this expansion and has grown the fastest in recent years — the Office of Tailored Access Operations, or TAO. This is the NSA's top operative unit — something like a squad of plumbers that can be called in when normal access to a target is blocked. According to internal NSA documents viewed by SPIEGEL, these on-call digital plumbers are involved in many sensitive operations conducted by American intelligence agencies. TAO's area of operations ranges from counterterrorism to cyber attacks to traditional espionage. The documents reveal just how diversified the tools at TAO's disposal have become — and also how it exploits the technical weaknesses of the IT industry, from Microsoft to Cisco and Huawei, to carry out its discreet and efficient attacks. The unit is “akin to the wunderkind of the US intelligence community,” says Matthew Aid, a historian who specializes in the history of the NSA. “Getting the ungettable” is the NSA's own description of its duties." - × × ×