Ok, get ready to fuss at me for being a jerk....
The average IQ score is 100, with a standard deviation of 15 points. This makes the normal range from 85 to 115. One more standard deviation on either end, from 70 to 130, encompasses dull normal and bright normal. Anything below two standard deviations, or <69, is considered mentally retarded. Anything above two standard deviations, or >130, is considered gifted. 95% of the general population has IQs that fall between 70 and 130. 2.5% fall within the mental retardation range and 2.5% fall within the gifted range.
"Normals" don't typically hang out and socialize with mentally retarded folks. "Normals" find mentally retarded folks frustrating and boring. Historically, normal folks have treated people with mental retardation pretty horribly (institutions, torture, extermination, ridicule, etc.). Imagine how angry and frustrated the normal population would feel if the world's politics, religious institutions, laws, social norms and commerce were all primarily maintained by the mentally retarded!
Now consider this, gifted individuals are intellectually as far from normal people, as normal people are from the mentally retarded! Being gifted and living in a world run by normals is exactly like being normal in a world run by people with mental retardation!
Can you imagine being of normal IQ and trying to argue politics or religion with a mentally retarded person who is incapable of comprehending your standards for logic and rational thought? It is the same for gifted people who debate normal people. Except, that the normals represent such a HUGE majority that their opinions are considered valid! The majority of the populous operates from same crude belief system... "Because we all agree, we must be right."