Make Yourself Think

How is it that there are such large swaths of the population that do not grasp the fact that you have control over what you think, say, and do? Especially considering that the vast majority of world religions are based on this very principle?

Is this just the Asperger's "separation of mind" thing going on in my own head that doesn't go on in everyone else's? Because I can't remember a time when I didn't control my thoughts. Emotions could get out-of-control overwhelming, yeah, but not words or thoughts.