Remarks by the President at the Pentagon Memorial (excerpt)

[T]he highest honor we can pay those we lost, indeed our greatest weapon in this ongoing war, is to do what our adversaries fear the most -- to stay true to who we are, as Americans; to renew our sense of common purpose; to say that we define the character of our country, and we will not let the acts of some small band of murderers who slaughter the innocent and cower in caves distort who we are. . . .

They may seek to exploit our freedoms, but we will not sacrifice the liberties we cherish or hunker down behind walls of suspicion and mistrust.  They may wish to drive us apart, but we will not give in to their hatred and prejudice. . . .

They may seek to spark conflict between different faiths, but as Americans 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 Qaeda, a sorry band of men which perverts religion.  And just as we condemn intolerance and extremism abroad, so will we stay true to our traditions here at home as a diverse and tolerant nation.  We champion the rights of every American, including the right to worship as one chooses -- as service members and civilians from many faiths do just steps from here, at the very spot where the terrorists struck this building. . . .

Those who attacked us sought to demoralize us, divide us, to deprive us of the very unity, the very ideals, that make America America -- those qualities that have made us a beacon of freedom and hope to billions around the world.  Today we declare once more we will never hand them that victory.  As Americans, we will keep alive the virtues and values that make us who we are and who we must always be.

http://www.whitehouse.gov/the-press-office/2010/09/11/remarks-president-pentagon-memorial