Most of the people who planned that attack are dead, and the remainder are protected by scum like occupy wallstreet or Obama, but no matter what, I promise you they will never be free again. They will be hunted down and killed off if ever identified, even if Obama gives them a pardon, and will be put down, chopped up, and fed to dogs. These men were Satanic, Nietzscheans in the most perverse way, and deserve no pity or allowances.
However, they are not one billion people. They are a sickness within it, but so is The Lord's Liberation Army of Christianity, but it's hardly representative of Christianity... you couldn't compare it with Mother Teresa's mission. There are a great many Muslims who do decent things. Some similar to your friends growing up even.