Somewhat like God, if 9/11 didn’t happen it would have had to be invented. The attack on the New York World Trade Center and the Pentagon were exactly what US neo-conservatives and US oil interests needed: an excuse for regime change in Afghanistan, and later, in Iraq, as part of an aggressive policy of military, political and economic consolidation and expansionism. It was the tail that wagged the dog.
In the aftermath of 9/11, the only remaining superpower attacked Afghanistan to remove the Taliban from power. The excuse was the capture of Osama bin Laden. The invasion occurred despite a proposal by the Taliban regime to surrender bin Laden to the United States if there was evidence that he was indeed responsible. The US rejected the proposal even before bin Laden accepted responsibility for the attack.