It is precisely scenarios like this that make the improper handling of sensitive information such a crime. Even if it isn’t the case, it is entirely plausible that it CAN happen. Hell, even the emailed photo of a submarine bulkhead can give someone, somewhere information that can cost the lives of Americans. That Hillary walks away from this is a travesty.
It’s also why there is nothing in the law about intent. Mishandling sensitive information, and really bad things may result, even if you didn’t intend for that to happen. Ignorance, carelessness, stupidity, lack of sophistication, whatever you want to call it are no excuse. FBI added interpretation to the law that were never designed to be there, and are not applied to others.