According to U.S. President George W. Bush and U.K. Prime Minister Tony Blair , the coalition aimed " to disarm Iraq of weapons of mass destruction , to end Saddam Hussein 's support for terrorism , and to free the Iraqi people . " Others place a much greater emphasis on the impact of the September 11 attacks , on the role this played in changing U.S. strategic calculations , and the rise of the freedom agenda . According to Blair , the trigger was Iraq 's failure to take a " final opportunity " to disarm itself of alleged nuclear , chemical , and biological weapons that U.S. and British officials called an immediate and intolerable threat to world peace
September 11 attacks
September 11 attacks
2003 invasion of Iraq