What is the President’s Greatest Responsibility?

"According to President Obama, he has no higher duty than to protect the American people. But that’s not what the Constitution says.

“As President, I have often said that I have no greater responsibility than protecting the American people,” wrote President Obama in the new“National Strategy for Counterterrorism” (pdf) that was released by the White House yesterday. A similar sentiment appears in the Introduction to the new Strategy, which states that the President “bears no greater responsibility than ensuring the safety and security of the American people.”

This seems like a fateful misunderstanding. As chief executive and commander in chief of the armed forces, the President obviously has responsibility for national security. But to claim that he has no greater responsibility than “protecting the American people” is a paternalistic invention that is historically unfounded and potentially damaging to the political heritage of the nation.

The presidential oath of office that is prescribed by the U.S. Constitution (Art. II, sect. 1) makes it clear that the President’s supreme responsibility is to “…preserve, protect, and defend the Constitution of the United States.” There is no mention of public safety. It is the constitutional order that the President is sworn to protect, even if doing so entails risks to the safety and security of the American people..."

http://www.fas.org/blog/secrecy/2011/06/pres_responsibility.html