You'd have to be very naive to think that national intelligence agencies don't have dedicated hacking and information security penetration operations. In fact, if the US lacked this capability our spymasters would be derelict in their duty. Most of the complaining about foreign hacking or signals intelligence is just playing to (the dumb or naive part of) the domestic audience.
It was always amusing to play spot the Fed at Def Con ;-)
The manpower necessary to practice traditional SIGINT can be found in well-defined places -- you need people with CS, EE, Physics and Math backgrounds. For crypto you need very smart guys with math ability. But hacking/cracking involves a certain obsessive-compulsive personality component: you have to focus really hard on ugly bits of (often poorly designed) code and immerse yourself in the inelegant details. There's also an associated anti-authoritarian streak, which clashes with the nature of government service. So it's challenging for the spooks to recruit and retain hacker/cracker talent. The suits coexist uneasily with the "wild-type" found at places like Def Con. (Did I ever mention I almost accepted a summer job offer from the Institute for Defense Analysis after I graduated from Caltech? That's yet another story ...)
Here's something about TAO ("Tailored Access Operations"!), within the NSA.
Foreign Policy: ... By the time Obama became president of the United States in January 2009, TAO had become something akin to the wunderkind of the U.S. intelligence community. "It's become an industry unto itself," a former NSA official said of TAO at the time. "They go places and get things that nobody else in the IC [intelligence community] can."
Given the nature and extraordinary political sensitivity of its work, it will come as no surprise that TAO has always been, and remains, extraordinarily publicity shy. Everything about TAO is classified top secret codeword, even within the hypersecretive NSA. Its name has appeared in print only a few times over the past decade, and the handful of reporters who have dared inquire about it have been politely but very firmly warned by senior U.S. intelligence officials not to describe its work for fear that it might compromise its ongoing efforts. According to a senior U.S. defense official who is familiar with TAO's work, "The agency believes that the less people know about them [TAO] the better."
The word among NSA officials is that if you want to get promoted or recognized, get a transfer to TAO as soon as you can. The current head of the NSA's SIGINT Directorate, Teresa Shea, 54, got her current job in large part because of the work she did as chief of TAO in the years after the 9/11 terrorist attacks, when the unit earned plaudits for its ability to collect extremely hard-to-come-by information during the latter part of George W. Bush's administration. We do not know what the information was, but sources suggest that it must have been pretty important to propel Shea to her position today. But according to a recently retired NSA official, TAO "is the place to be right now."
There's no question that TAO has continued to grow in size and importance since Obama took office in 2009, which is indicative of its outsized role. In recent years, TAO's collection operations have expanded from Fort Meade to some of the agency's most important listening posts in the United States. There are now mini-TAO units operating at the huge NSA SIGINT intercept and processing centers at NSA Hawaii at Wahiawa on the island of Oahu; NSA Georgia at Fort Gordon, Georgia; and NSA Texas at the Medina Annex outside San Antonio, Texas; and within the huge NSA listening post at Buckley Air Force Base outside Denver.
The problem is that TAO has become so large and produces so much valuable intelligence information that it has become virtually impossible to hide it anymore. The Chinese government is certainly aware of TAO's activities. The "mountains of data" statement by China's top Internet official, Huang Chengqing, is clearly an implied threat by Beijing to release this data. Thus it is unlikely that President Obama pressed President Xi too hard at the Sunnydale summit on the question of China's cyber-espionage activities. As any high-stakes poker player knows, you can only press your luck so far when the guy on the other side of the table knows what cards you have in your hand.