Saddam Hussein was originally an American stooge who loved Frank Sinatra, cigars and western business suits. The Americans used him to check Iran and showered him with weapons .
After 9/11, the Americans needed someone to unleash their rage upon. The attackers were mainly saudi arabian, but the Americans could not attack Saudi Arabia because of their corporate business interests there.
So they decided to take on Saddam Hussein instead, vilifying their former asset with a well-funded propaganda campaign and brought about the war in the name of freedom and democracy.
The removal of Saddam proved to be a major blunder later on, as it destabilised the whole region. Saddam had controlled the sunni and shia extremists and prevented them from coming to power. With the absence of Saddam, these elements came to power in the form of ISIS and extremist islamist ideologies which needed new wars to take care of.