C.I.A. Warning on Snowden Fell Through the Cracks - NYT | Mike Nova comments: What caused this "distinct change"?

C.I.A. Warning on Snowden Fell Through the Cracks

By ERIC SCHMITT

When Edward J. Snowden worked as a technician for the agency, he was suspected of trying to break into classified files, but a report was never forwarded to the National Security Agency, officials said.

WASHINGTON — Just as Edward J. Snowden was preparing to leave Geneva and a job as a C.I.A. technician in 2009, his supervisor wrote a derogatory report in his personnel file, noting a distinct change in the young man’s behavior and work habits, as well as a troubling suspicion.

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Mr. Snowden got an information technology job at the C.I.A. in mid-2006. Despite his lack of formal credentials, he gained a top-secret clearance and a choice job under State Department cover in Geneva. Little is known about what his duties were there.

Mavanee Anderson, who worked with Mr. Snowden in Geneva and also had a high security clearance, said in an article in The Chattanooga Times Free Press of Tennessee in June that when they worked from 2007 through early 2009, Mr. Snowden “was already experiencing a crisis of conscience of sorts.”

“Anyone smart enough to be involved in the type of work he does, who is privy to the type of information to which he was privy, will have at least moments like these,” she said.

Later, Mr. Snowden would tell the newspaper The Guardian that he was shocked and saddened by some of the techniques C.I.A. operatives in Geneva used to recruit sources. “Much of what I saw in Geneva really disillusioned me about how my government functions and what its impact is in the world,” he told The Guardian. “I realized that I was part of something that was doing far more harm than good.”

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Mike Nova comments: 

What caused this "distinct change"? 

Did he become a target of subtle recruitment efforts at that time? 

If it is so, why and how was it missed?