what does this role entail?
It gives the ultimate responsibility for the direction and disposition of the military.
President of the United States
mmander-in-chief of the United States Armed Forces. The power to declare war is constitutionally vested in Congress, but the president has ultimate responsibility for the direction and disposition of the military. 
who was president of the us in 1985 Ronald Wilson Reagan . where was he born? Tampico, Illinois. did he have a career in movies prior to entering politics? Yes, he signed a deal with the Warner Bros. studios. what has he acted in? "Love Is on the Air", "Dark Victory", "Santa Fe Trail", and "Knute Rockne, All American". which state was he the governor of? California. who was president of the country before him? Jimmy Carter. what is the other title given to a person holding this office? The commander -in-chief. what are they the commander of? Of the United States Armed Forces.
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President of the United States [SEP] Commander-in-chief
One of the most important of executive powers is the president's role as commander-in-chief of the United States Armed Forces. The power to declare war is constitutionally vested in Congress, but the president has ultimate responsibility for the direction and disposition of the military. The exact degree of authority that the Constitution grants to the president as commander-in-chief has been the subject of much debate throughout history, with Congress at various times granting the president wide authority and at others attempting to restrict that authority. The framers of the Constitution took care to limit the president's powers regarding the military; Alexander Hamilton explained this in Federalist No.