ForeignPolicy.org recently published this published a great article discussing how the world would have been different if Islam never existed. Would 9/11 have happened? Would the Arab Spring have happened? And would the many clashes of civilization between the Muslim world and the West have occurred?
The author, Graham Fuller, makes a very convincing and informed argument that the world would have been more or less the same. The course of history may have changed slightly but it would ultimately be the same. Go ahead and read it. It’s a lengthy read, but totally worth it.