President Obama said Tuesday the 9/11 anniversary is always a difficult day, but the United States has emerged stronger in the 11 years since the terrorist attacks on New York City and the Pentagon.
"Painful as this day is -- and always will be -- it leaves us with a lesson that no single event can ever destroy who we are," Obama said during a solemn ceremony at the Pentagon, one of the buildings targeted by airplane hijackers 11 years ago. "No act of terrorism can ever change what we stand for."
The historical legacy of the attack will not be "fear or hatred or division," Obama said, but rather "a safer world, a stronger nation and a people more united than ever before."
As planes taking off from nearby Reagan National Airport roared overhead, Obama also said: "This anniversary allows us to renew our faith, that even the darkest night gives way to a brighter dawn."
The president -- who also led a moment of silence at the White House -- said "this is never an easy day," especially for the relatives and friends of the nearly 3,000 people who lost their lives that day.
"Your loved ones will never be forgotten," Obama said. "They will endure in the hearts of our nation, because through their sacrifice they helped us make the America we are today, an America that has emerged even stronger."
"I've always said that our fight is with al-Qaeda and its affiliates," Obama said, "not with Islam or any other religion."
After the Pentagon ceremony, the president and first lady Michelle Obama stopped at Arlington National Cemetery, visiting sections where soldiers who fought in Iraq and Afghanistan are buried.
On several graves, the president placed "challenge coins," medallions bearing insignia passed out by commanders as motivation or to honor achievement.
Earlier, the president, Mrs. Obama, and the entire White House staff gathered on the South Lawn at 8:46 a.m., the time that American Airlines Flight 11 struck the north tower of the World Trade Center in New York City.
Vice President Biden visited the site of another attack, the field in Somerset County, Pa., where United Airlines Flight 93 crashed after a rebellion by passengers, en route to a planned strike in Washington, D.C.
Speaking to the loved ones of those who died on 9/11, Biden said his hope is that "as every day passes, the depth of your pain passes."
At the Pentagon ceremony, Defense Secretary Leon Panetta said terrorists attacked "the symbols of American strength," but instead produced only "a new sense of unity and resolve, that this would not happen again."
From the pool report:
Soon after 8:30 a.m., hundreds of White House staff gathered on the South Lawn, in the shade of the portico and in patches of sun. Most stood with hands crossed in front of them. Only the sound of a jet, leaving Reagan National, rose above the sounds of whispers among staff and media.
At 8:45 a.m., a pair of Marines appeared before the door beneath the portico leading onto the South Lawn. Another pair of Marines presented the colors -- one holding the flag, another a trumpet.
The hundreds gathered remained silent, now only the sound of distant traffic the background noise. ...
President Obama and Mrs. Obama walked slowly down the grassy strip, the president in a dark suit and the first lady in a dark purple dress, as three bells tolled. They stood with heads bowed,facing the National Mall in the distance.
A few minutes later, the Marine trumpeter began playing taps, and the First Couple, along with many staff, lifted their heads and placed their hands over their hearts. Then the First Couple turned, took each others hands,and walked back along the grassy passage between the quiet staff and back inside.
The staff filed back inside soon after.