Very damning: Hillary Clinton clearly knew that she was sending secret information via insecure emails and that she knew it was wrong

From Fox News:

In response to Clinton's request for a set of since-redacted talking points, Sullivan writes, "They say they've had issues sending secure fax. They're working on it." Clinton responds "If they can't, turn into nonpaper [with] no identifying heading and send nonsecure."Ironically, an email thread from four months earlier shows Clinton saying she was "surprised" that a diplomatic oficer named John Godfrey used a personal email account to send a memo on Libya policy after the fall of Muammar Qaddafi. . . .

These two paragraphs are very damning.  They show both that she knew she was telling people to send secret information in a way that wasn't secure, that her previous statements that the secret material wasn't labeled may have been because she thought she could hide that it was secret and protect her from liability (she is wrong legally even if she thought this excuse could confuse the issue), and finally that she called out others for doing what she was doing.