they flew two of them into the twin towers of the world tried center in new yorkity. another plane crashed into the defense department in washington. a fourth plane went down in a field in pennsylvania. in total, almost 3,000 people were killed in the attacks. people observed the minute of silence at 8:46 local time, the exact moment when the first plane hit one of the towers. victims then read out the names of lost loved ones. the victims' names are inscribed around the monument. u.s. president obama and vice president joe biden marked a moment of silence at the white house, obama then attended a ceremony at the pentagon. >>> and president obama has addressed the country about his plans for syria. he laid out the rationale for a strike against the regime of president bashar al assad and he asked congress to delay a vote on whether to approve military action. >> i determined that it is in the national security interest of the united states to respond to the assad regime's use of chemical weapons to a targeted military strike. the purpose of this strike would be to det