In his weekly radio and Internet address, Obama said the 11th anniversary of the attack next week is "a time to remember the nearly 3,000 innocent men, women and children we lost, and the families they left behind."
"It's a chance to honor the courage of the first responders who risked their lives -- on that day, and every day since," he said. "And it's an opportunity to give thanks for our men and women in uniform who have served and sacrificed, sometimes far from home, to keep our country safe."
Obama said Tuesday's anniversary is "a time to reflect on just how far we've come as a nation these past 11 years."
He said the last decade has been difficult but the United States has "come back stronger as a nation."
"We took the fight to al-Qaida, decimated their leadership, and put them on a path to defeat," the president said. "And thanks to the courage and skill of our intelligence personnel and armed forces, Osama bin Laden will never threaten America again."
Obama said the United States, "instead of pulling back from the world," has strengthened international alliances and improved domestic security.
"As Americans, we refuse to live in fear," he said. "Today, a new tower rises above the New York skyline. And our country is stronger, safer and more respected in the world.
"Eleven years later, that's the legacy of 9/11 -- the ability to say with confidence that no adversary and no act of terrorism can change who we are," Obama said. "We are Americans, and we will protect and preserve this country we love. On this solemn anniversary, let's remember those we lost, let us reaffirm the values they stood for, and let us keep moving forward as one nation and one people."
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