JUDY WOODRUFF: A farewell to one of the most influential military leaders in modern U.S. history.
Kwame Holman has that story.
KWAME HOLMAN: His four years overseeing the U.S. military have taken Adm. Mike Mullen around the world many times over, meeting with troops in two war zones, attending elaborate military ceremonies in China, coordinating disaster aid in earthquake-stricken Haiti.
But Mullen's greatest role was in helping wind down the war in Iraq and expand the war in Afghanistan. At his Senate confirmation hearing in 2007, he expressed characteristic candor about Iraq.
ADM. MICHAEL MULLEN, Joints Chiefs Chairman: Based on the political -- lack of political reconciliation at the government level, obviously, although I spoke earlier about some of it going on at the local level, which I think is important, I would be concerned about whether we'd be winning or not.
KWAME HOLMAN: On Afghanistan, Mullen played a bigger role, saying the U.S. needed to refocus its energies there and in the region. When President Obama asked for an Afghan war review, Mullen stuck by commanders in the field who demanded resources for a counterinsurgency approach.
David Ignatius of The Washington Post has traveled to the region frequently with the admiral.
DAVID IGNATIUS, The Washington Post: There is this view that the White House has that Mullen and the military kind of boxed the president in, and narrowed their options and pushed them down the road toward this 30,000 troop surge.
It didn't look that way to me as I was reporting it. It looked more like a kind of classic chain of command thing.
KWAME HOLMAN: In his final words to Congress last week, Mullen called out Pakistan for aiding the Haqqani terrorist network in recent attacks in Afghanistan.
ADM. MICHAEL MULLEN: The Haqqani Network, for one, acts as a veritable arm of Pakistan's internal services intelligence agency.
KWAME HOLMAN: Mullen made 27 trips to Pakistan during his tenure, cultivating a relationship with top military officials there, including Gen. Ashfaq Parvez Kayani. That relationship became strained after the killing of Osama bin Laden by American special forces inside Pakistan.
Kayani received no heads-up from Mullen, nor did the Pakistani government know of the raid on the compound in Abbottabad.
Ignatius says the Pakistan relationship has been a bitter pill for Mullen.
DAVID IGNATIUS: So, he'd go out to see Kayani. It sometimes seemed, every few weeks, he was flying halfway around the world to Pakistan.
I went on a number of those trips with him. And I'll tell you, it's a long way to go for what was often a meeting of just a few hours. But Mullen put in the time and believed that he was making progress.
KWAME HOLMAN: Adm. Mullen's tenure at the Pentagon may be best remembered for his strong advocacy for ending the military's don't ask, don't tell policy. For 18 years, it barred homosexuals from serving openly. It ended last week, 18 months after Mullen spoke out.
ADM. MICHAEL MULLEN: No matter how I look at this issue, I cannot escape being troubled by the fact that we have in place a policy which forces young men and women to lie about who they are in order to defend their fellow citizens.
KWAME HOLMAN: Mark Thompson is TIME magazine's defense reporter.
MARK THOMPSON, TIME: Mullen gave the president and Secretary of Defense Robert Gates all of the sort of four-star coverage they needed to push ahead with this, knowing that the nation's top military officer was in their camp.
KWAME HOLMAN: Today, at a time-honored ceremony at Joint Base Myer in Virginia, the chairman handed over his duties to Army Gen. Martin Dempsey.
Mullen began his military service at the U.S. Naval Academy in 1964. President Obama honored that long service, in particular Mullen's dedication to men and women in uniform.
PRESIDENT BARACK OBAMA: I have seen it in the quiet moments with our wounded warriors and our veterans. I saw it that day in the Situation Room, as we held our breath for the safe return of our forces who delivered justice to Osama bin Laden. I saw it at Dover, as we honored our fallen heroes in their final journey home.
Mike, you have fulfilled the pledge you made at the beginning: to represent our troops with unwavering dedication.
KWAME HOLMAN: In his last words as chairman, Mullen asked all Americans to look after the nation's troops.
ADM. MICHAEL MULLEN: We talk about the resilience of our troops and their families as if it is something apart from the rest of society. It isn't -- or, at least, it shouldn't be. Where do you think those troops learned to be so brave? In your homes, in your schools, in your communities.
KWAME HOLMAN: Just yesterday, on his final full day as chairman, Mullen and his wife, Deborah, said one more farewell to troops buried in Section 60 of Arlington National Cemetery, a parcel set aside for those killed in Iraq and Afghanistan.