I don't want to go into further detail. But the power of the military can't be over ruled. Random examples of powers exercised by the executive (politicians) can't generalize the norm. Even the powers exercised by the President is according to the lines of the Pentagon.
Anyway, I don't want to go into detail, who is the real master of this power politics. My point, which could be wrong, is there is no way to play with the fire (military).
One example, I want to quote from Pakistan, sacking of Admiral Mansoor ul Haq (ex joint chief of staff committee), does that prove the power of executive on military establishment.