Hillary Clinton testified before the Benghazi Committee on Thursday because she is the victim of a vast right-wing conspiracy that refuses to let her enjoy the lifestyle of an everyday millionaire who just wants to be president. This explains why Hillary was compelled to secretly set up a private email server in her basement and conduct government business over an unsecured network. She couldn't risk becoming the target of a so-called "government transparency" scam. It was a courageous decision that proved her willingness to fight on behalf of every government official who has ever been forced to suffer the indignity of a FOIA request.
That is actually how one former Obama administration official explained Hillary's actions in an interview with Vanity Fair (emphasis added):
The e-mail scandal is the perfect distillation of how Hillary’s wall of protection makes matters worse. Her exclusive use of the Clintons’ personal e-mail server while secretary of state appears born out of a defensive instinct for secrecy. The eye-rolling dismissiveness with which Clinton herself initially greeted the revelation, and the stonewalling nature of the response by her surrogates, have only fed the scandal more oxygen. Before Clinton began at the State Department, she and her aides arranged to create a private e-mail account on a server linked to her home in Chappaqua. An Obama-administration official whose tenure coincided with Clinton’s at the State Department empathized with Hillary. "I understand why she did this. We are targeted all the time in the U.S. government, and there is no more vulnerable feeling than putting your thoughts on a government e-mail."
Yes, the anonymous official is correct. Putting your thoughts on a government e-mail really is the most vulnerable feeling of all the feelings.