Al-Qaeda built its ideological doctrine largely in opposition to the Muslim Brotherhood’s pervasive and once dominant approach to Islam’s political revival. For many years, the Muslim Brotherhood attempted to ignore al-Qaeda’s challenge and concentrated instead on beefing up its own organizational and ideological alternative to the ruling secular regimes in the Arab world and elsewhere. This pattern changed dramatically after September 11, 2001, when it became more difficult for the Brotherhood to disregard al-Qaeda and the two movements began competing more openly for leadership of the overall Islamist movement.