The issue here seems to be violations of security of high state documents, which could contain issues endangering elements of national security. This is NOT a joke, or "just one of those things." There are very good reasons in this very dangerous and nasty dark world for prohibiting persons (of ANY rank) taking documents to any non-secure location. ALL documents must be thoroughly vetted in secret by professionals before their national security implications (if any) are assessed. Violations of this are against a serious law. It's NOT a casual act; that comment would be extremely naive. And, it is not acceptable for anyone to make Security assessments on their own. This person has been briefed on this issue long ago when taking office, and has been told more than once after office that he was wrong to take these documents and must return them, as they are not his property for good state department reasons.
As an aside: when this guy was elected, I heard two different former directors of security elements in our country (one a three letter agency and one a military high-rank) who said that the "personality" of this individual was a concern. The "loose cannon" nature of his speaking in public was shocking enough that talk within a certain three-letter agency was whether they needed (for security purposes only --- as that's all they care about in that place) NOT to include certain types of information in briefings. This worry was almost immediately actualized when the new President made off-the-cuff revealing comments about US military plans.
Republican supporters REALLY need to get back to their roots and Dump Trump out of them. This guy's no republican anyway; just a self-aggrandizing megalomaniac looking only to his own ego story. The True Republican/ True Democrat dichotomy is a good balancing of power when both are advocating their root policies AND are talking to one another. We must get back to that to have a well-functioning and civil governance. This @sshat is the never-wavering Divider of all that. (Even destroying or trying to destroy everyone in the Republican Party who doesn't trail obediently in his ego's wake. How people don't see this stuns me.)
.... but I'm still reserving judgement on the reasonableness of this current search order and the extent of damage possible, until more comes in. I still stand by the above paragraphs whether he was badly-treated by the Justice Department on this search operation or not. I don't want Rogue operations in my ideal USA either, so let's see if this was rogue or legal and just.