New chair of the Joint Chiefs is sworn in

In a ceremony at Fort Myer, Va., President Obama lauded Mullen for his steadiness, resilience, and humility.

“Be assured, our military is stronger, and our nation is more secure because of the service that you have rendered,’’ the president told Mullen, who is ending a 43-year military career. Obama called Dempsey one of the military’s most battle-tested officers.

Hours earlier, officials confirmed that radical cleric Anwar al-Awlaki, an American citizen and prominent figure in Al Qaeda’s affiliate in Yemen, was killed in an airstrike there.

Defense Secretary Leon Panetta also praised Mullen and welcomed Dempsey as the next chairman. Of Dempsey, he said, “He knows about people; he knows about hard work; he knows about sacrifice.’’

In his final speech as chairman, Mullen urged Americans to do more to help returning war veterans. “War has changed them and their loved ones forever, but it has not changed their dreams,’’ Mullen said. “You can help make those dreams come true. Hire them. Help them buy a home. Get them started on the path to an education. Give them a chance.’’

After his swearing-in, Dempsey delivered brief remarks pledging that on his watch the military will remain strong, despite the pressure of budget cuts.

“We’ll change, and we’ll be challenged,’’ he said. “But when I complete my tenure as chairman of the Joint Chiefs of Staff, I intend to be able to say exactly the same thing: We will be the joint force the nation needs us to be, so help me God.’’

Before taking over as chairman, Dempsey made clear that he differs with his predecessor on one of the most important issues of the day: the threat posed to national security by a growing national debt.

At his Senate confirmation hearing in July, Dempsey was asked whether he agreed with Mullen’s oft-repeated assertion that the debt crisis is the single biggest threat to US national security. “I don’t agree exactly with that,’’ Dempsey said.

In his view, developed in the course of a 37-year career that includes two tours of command in Iraq and one in Saudi Arabia, American global power and influence are derived from three strengths: military, diplomatic, and economic. “You can’t pick or choose,’’ he said; none of the three is paramount.

It is too early to know how much change Dempsey will foster in his role as the top US military officer, but it is certain that pressures to cut the defense budget - and what that implies for the military and for American foreign policy - will be a dominant issue from Day One.

By law, the chairman of the Joint Chiefs serves as the senior military adviser to the president, the president’s National Security Council, and the secretary of defense.

But the chairman is not directly in the chain of command that extends from the president to the secretary of defense to commanders in the field. He is the public face of the US military and weighs in on major policy decisions but is not actually in charge of any troops.

In the final week of his tenure, Mullen made his biggest headline by telling a Senate committee that the Haqqanis are a “veritable arm’’ of Pakistan’s intelligence service and by asserting that Pakistani intelligence supported and facilitated a string of Haqqani attacks on Americans in Afghanistan.

His statement infuriated the Pakistani government and arguably set back, at least temporarily, an already troubled US-Pakistani relationship.

Dempsey’s views on Pakistan’s importance to success in Afghanistan appear to be similar to Mullen’s, although he has been less specific about the role of the Haqqanis.