What was the result of Al'Qaeda's claim to be behind the September 11th terrorist attacks

Two weeks after the September 11 attacks, the Federal Bureau of Investigation connected the hijackers to al-Qaeda,[1] a global, decentralized terrorist network. In a number of video, audio, interview and printed statements, senior members of al-Qaeda have also asserted responsibility for organizing the September 11 attacks.[2][3][4] It is believed that Osama bin Laden, Khalid Sheikh Mohammed, and Mohammed Atef were the ones who plotted the attacks after meeting together in 1999.[5] It is also believed Khalid Sheikh Mohammed was the one who planned the attacks[5] and that Atef was the one who organized the hijackers.[5]