This is talking about 'off post' being banned. Not 'on post'.
I'm aware of that -- I thought I made that clear in my comment: "The policy of 'no concealed carry on post' even in those states that allow it has been in place for many many years now. The Joint Chiefs have never overturned that. Why do you think they would overrturn this?"
The point being that they never overturned something wholly under their jurisdiction before, so why would they bother now? Besides, as I said, the JCS does not get involved in things like this. They are a war-fighting structure. Administrative rules like this from a local commander are not what they deal with. Never have been.