Time magazine (November 9) carries an article dealing with the reason why the CIA Director Gen. David Petraeus had to resign under the caption, “Resignation at the CIA: Why Petraeus had to go.” There is a paragraph:
“In the world of spies, there is a short list of weaknesses you can exploit in your opponents: People have spent centuries figuring out how to get people to commit treason. Arguing the other side is better for humanity, offering to help someone who’s deeply in debt or paying hard cash to the greedy are classic methods. But few are more effective than blackmail, and even in the post-Lewinsky era in Washington, infidelity leaves officials vulnerable.
You can’t lead an organization whose case officers must be impervious to blackmail if you’re vulnerable to it yourself.”
I cannot understand what the last line, “You can’t lead an organization ‘whose case officers must be impervious.’ “means? What does “case officer" mean?