• The U.S. Constitution lays out the duties of the president.Lincoln Memorial - Washington DC image by Misha Tyukin from Fotolia.com
  
  Article II of the United Stated Constitution lays out the duties and powers of the executive branch in general and the president in particular. As stated in the president's oath of office, the president's duty is to "preserve, protect, and defend the Constitution of the United States." Presidential duties however, are a bit more complicated than that.
  
  

Commander in Chief

• The president commands the military.russian army image by Alexey Klementiev from Fotolia.com
  
  Section 2 grants the president the authority of "commander in chief of the Army and Navy of the United States, and of the militia of the several states." This gives the president command of the United States armed forces as well as state militias when called to service the nation rather than the state. As commander in chief, the president directs military strategy and planning, although he acts as the Constitution stipulates, with the opinion of the secretary of defense.
  
  

Veto

• The framers of the Constitution were always mindful of one branch of government becoming too powerful, and to that end, Article I, Section 7 gives the president the power to veto a bill "with his objections" and send it back to the house of Congress that initiated the bill. However, the president's veto power isn't absolute. The same section allows that if both houses of Congress pass the bill with at least two-thirds vote from each house, the bill can pass over the president's veto.
  
  

Executive

• The Constitution allows the president to nominate Supreme Court justices.us supreme court image by jedphoto from Fotolia.com
  
  The job of president is also an executive position responsible for the daily maintenance of the federal government. In that capacity, the Constitution allows the president to negotiate with other nations and enter into treaties. Furthermore, the Constitution charges the president with the responsibility of filling many high-level federal positions, including the Cabinet, which includes the heads of 15 major federal agencies, including the Department of State and Department of Homeland Security. The president nominates federal judges and Supreme Court justices as stipulated by Section 2. The president may also fill any federal vacancy that occurs when Senate is on recess, if that vacancy typically requires "advice and consent of Senate."
  
  

State of the Union

• Article II, Section 3 of the Constitution requires the president address Congress "from time to time" to keep it informed of the state of the Union and set forth issues "he shall judge necessary and expedient." The Constitution doesn't provide specifics, but presidents since 1790 have presented annual State of the Union addresses. The Constitution does not stipulate that the address must be given in person, but most presidents have given the address in person.