Oh, let's see what NPR and Politifact said back in 2017, shall we?
NPR:
WITTES: Well, so the president controls classified information. The - almost the definition of classified information is material the president wants to protect. So if the president wants to disclose it, he gets to disclose it. And disclosures that would be a very serious crime if anyone else did them are almost certainly not if the president does them. So, you know, if the question is, is there a criminal problem here, the answer is almost certainly not.
Politifact:
View attachment 684777
The blockbuster article in The Washington Post saying President Donald Trump had "revealed highly classified information
www.politifact.com
The President is the head of the Executive Branch. As such, he is the utmost authority on classification of documents.