Call me an old badger, but the words in the Commissioning Oath are the clue that however senior the leaders, there are some obvious limits to what you can decide to like or dislike.
...and you to observe and follow such Orders and Directions as from time to time you shall receive from Us, or any superior Officer, according to the Rules and Discipline of War, in pursuance of the Trust hereby reposed in you.
Admittedly "the Rules and Discipline of War" caveat is may allow some discretion, but "the Trust hereby reposed in you" nicely counters that.