Oops, I see I replied to the wrong post, somehow, it was supposed to go to rjsimmon at post 184, not you at 185. for convience I’ll repeat the question here.
If the President is not Commander in Chief of the Army and Navy when there is no war or armed conflict, then who is under the Constitution, and where does it indicate this?
Only when the military is engaged in open warefare under the authority of the United States do they need a unified Commander in Chief. Otherwise, the doctrines of the individual services dictate their mission and the Commandant of the Marine Corps, Chief of Naval Operations, Chief of Staff of the Army, and Chief of Staff of the Air Force all command their services.
Under each head of their service are, what was formerly called, Commanders in Chief (CINC), but that was changed a few years back. Now they are component commanders or Unified Combatant Commanders for such commands as CentCom, SouthCom, etc.
The Constitution established a CINC for wartime since the concept of a standing army was repugnant to the founders. They understood the necessity of an army, but did not like it to persist, hence the militia.