solemn anniversary of the day when foreign terrorists attacked our freedom. a day when 2,977 people died at the world trade center, at the pentagon, and in a field outside shanksville, pennsylvania. the white house releasing a video ahead of the 20th anniversary of the 9/11 attacks. >> unity is what makes us who we are. america at its best. to me, that's the central lesson of september 11th. it's that at our most vulnerable, in the push and pull of all that makes us human, in the battle for the soul of america, unity is our greatest strength. unity doesn't mean we have to believe the same thing. but we must have a fundamental respect and faith in each other and in this nation. >> hmm. unity means that we don't have to all believe the same thing but we have to have a fundamental respect.