I don’t see how an SOS could function without a security clearance. They are constantly involved in security situations. Just think about Benghazi. You KNOW she had to have been all over secret info on that. And that’s just one example. In 2016, when her campaign was asked if she still had a security clearance, their reply was, “no comment”. That speaks volumes, IMHO.
I think that people just "took it for granted" that she had one, because she is who she is. Later, everyone just assumes that she had a security clearance all along. Presidents don't go through clearances, only their assistants. What do you do with a First Lady?
Anyone who has a top security clearance would know that it is illegal to put secrets on your personal computer. But, she missed that lesson cuz she never went through any training.
Laws are for peons.