Now that I have read the thread fully after being one of the first posters, I see a bit of a trend.
All about the intelligence?
Nah. Not the intelligence. Anyone can be intelligent but to be socially able and politcally smart are two things that intelligent people sometimes lack.
Personally, I think it's more of the life experience factor.
Little people that are thirteen years old have no experience. They would have lost at life if it weren't for their parents.
People that have no idea about life shouldn't vote.
Intelligence can go on holiday. Life isn't all about being intelligent.