On a personal level I know when someone goes on extreme end of something I have an inkling towards, it helps me realize how wrong it is. Stereotyping is an example – seeing people sometimes being extremely racist towards minorities helps me put aside my memories of a robbery that happened to me years ago.
Is this same type of polarization known to occur on a cultural level? When I see the religious extremism in particular in the Middle East, I wonder if this creates a moderating force on the rest of the world, preventing say more Muslim areas, or even Christian ones, from living with such extreme ideologies.