A new report from Snowden states that the infamous Internet blackout that occurred in Syria during the Arab Spring uprisings was caused by the NSA and not the Syrian Government as reported by the US media at the time.
Apparently the NSA was trying to redirect web traffic in order to spy on it and accidentally 'bricked' the router of a large ISP
You need to be somewhat cautious about relying too much on Snowden et al when looking to him and others like him in similar positions. Espionage is a very dark game. The term "Black Ops" isn't just something made up in a Tom Clancy novel.
Consider the following possibility - as this sort of thing happens all the time - Edward Snowden might just as easily have been a CIA operative working within the NSA as much as he is perceived to have been an above board whistle blower intent on "doing the right thing". Intra-agency rivalries are legion especially in military-intelligence circles. The old Soviet KGB and GRU (Soviet Military Intelligence, in many ways far more ruthless than even the KGB) utterly despised each other. The NSA and CIA have been institutional rivals for decades.
Check out Brad Thor's intriguing work called "Black List". In the real world this stuff happens far more than most people realize.