When you write government emails using sensitive information, you must use the secure email your government employer uses. When you use ever more sensitive information in your email, you must follow the protocol for that information.
Creation of an email means you are the one who must “put the markings” on it. There is not someone to look at everyone’s email and put it there for you. Every government employee creates documents that must be properly marked and handled.
Do we really care what was IN those emails instead of concentrating on the fact that she was mishandling government property (probably a lesser offense)? Put it in simple terms, she broke the law and needs to be held accountable. DO SOMETHING DAMMIT!