World population growth
 

Religious propaganda. I like how they leave out stuff that doesn't fit their story, like what happens to Muslims when they become westernized.
They start drinking, having less kids, and abandoning religion altogether in a couple of generations. Once you get a taste of freedom you never want to go back. The only reason they have so many children is because the women don't have a choice. Hell, they can't even leave the house without an escort and getting an education or career will likely get a women killed or seriously maimed.