"Being an FBI agent is a very honorable and well-respected profession"

Unless you are doing this:

http://blogs.citypages.com/blotter/2011/01/secret_government...

It is not as though this is some kind of new, unprecedented behavior either:

http://www.cnn.com/2008/US/03/31/mlk.fbi.conspiracy/

https://en.wikipedia.org/wiki/J._Edgar_Hoover

So let's say a young man is thinking about joining the FBI; he wants to do good for the world, maybe help catch a serial killer or take down a child abuse group. How does he know he will not be asked to conduct surveillance on an anti-war group? How does he know he will not be asked to dig up some dirt on a civil rights leader?

This "honorable profession" you are defending has always had a dark side.