How do we gain "political" intelligence?

I read this question in a recent Linkedin group.  It reminded me of a study in a great EI book-- "Opening Up: The Healing Power of Expressing Emotions" by James Pennebaker.  The study indicated that when we deny or repress our emotions, our ability to conduct complex analysis can be diminished and we can be conned by salespeople, politicians, etc.  One explanation is that as energy is expended in one part of the brain (working at repressing the disturbing emotion), other brain functions may not work as well.  This makes sense to me.