"The World Changed on 9/11."
The world did not change on 9/11/2001. Everything that was part of the geopolitical landscape on 9/12/2001 had been there on 9/10/2001. What happened on 9/11/2001 was that America's ignorance about the forces and factions at work in the world was exposed.
However, the answer to ignorance is understanding and the neoconservatives didn't want to learn anything that might deter them from their dream of reshaping the world. So they sold the lie that everything had changed so that what was already known could be disregarded.