President Barack Obama marked the anniversary of the September 11th terrorist attacks with a speech at the Pentagon in Arlington, Va.
The president said it is natural to focus on images of that awful day, when al-Qaida killed thousands on U.S. soil, including 184 who were killed when a hijacked plane slammed into the Pentagon.
Obama said the memorials should remind still-grieving families to focus on the fullness of the lives of their loved ones before they died.
He also reiterated that the United States is not an enemy of Islam, but of Islamic extremists who use violence.
"We are not and never will be at war with Islam. It was not a religion that attacked us that September day. It was al-Qaida, a sorry band of men which perverts religion," said Obama.
The president said as Americans condemn extremism abroad they should also remember the American values of acceptance and diversity at home, including the right of Americans to worship as they choose.
Obama called the anniversary a day of remembrance as well as a day to unite and reflect as a nation.
Meanwhile, First Lady Michelle Obama and former First Lady Laura Bush joined hundreds in Shanksville, Pa. to remember the 40 victims of United Flight 93.
There was a moment of silence followed by the reading of the names, and each name was accompanied by the tolling of a bell.
Both first ladies praised the heroism of the passengers and crew, who tried to overtake the hijackers and regain control of the plane before it crashed in Shanksville.
"The men and women on that plane never met the people whose lives they would save, yet they willingly made the sacrifice," said Michelle Obama. "And before September 11th, the people of this community didn't know any of the families here today, yet they embrace them as their own."
"Americans have no division. Together, we recall the events that changed each one of us and that united our nation," said Bush. "Together, we honor the lost in silence and we remember that our quiet and peace is always defended by the courage of the brave."
Flight 93 was headed from Newark, N.J. to San Francisco when it was hijacked.
It is believed the hijackers intended to fly it to the Washington, D.C. area, possibly for an attack on the White House or the Capitol.
The president's call for unity was also echoed in the Republican weekly address.
Arizona Senator Jon Kyl said Americans need to come together as a nation to confront a common enemy.
"The ninth anniversary of 9/11 should cause us to think hard about the enemy that attacked us and would do so again if we relax our efforts," said Kyl. "We need to remember that direct terrorist attacks are but one of the tactics of this determined enemy."
Kyl said September 11th should also honor U.S. troops fighting overseas.
Without mentioning the Obama administration, Kyl criticized the handling of the war on terror, saying some urgency and commitment have been lost.