This thread is misunderstanding the job of Secretary of Defense. They aren't interns learning from the generals how to lead an army or plan logistics. They're project managers who ensure the generals are aligned with the President's goals.
I would say that they oversee the Pentagon and ensure that the military stays in civilian control. In the past, theories from war games percolate through the Joint Chiefs, who meet with SECDEF before presenting options to the President.
I was surprised Hegseth even desired a side channel that had the potential downside that he could accidentally text the coordinates of a carrier. Stuff like that gets Generals relieved immediately.
Equally bewildered as there is no real upside to this and the other folks on the line dont have any purpose of knowing prestrike information.
I am not as educated in these manners but this type of information seems to be of the type you don’t text on commercial applications and would be on a need to know basis. Maybe you can communicate the idea that something is planned to happen but not timelines of the specific assets.