Much of what passes for political discussion in this country is not civil, nor is it constructive, but is instead rude, vitriolic, partisan, and divisive. This type of atmosphere is not conducive to cooperation, compromise, and finding the best course of action through open inquiry in the market place of ideas. In essence, it is not democratic.
What can we do to improve this situation? First, I believe one should always keep Sidney Hook's rules for democratic discourse in mind. Simply following these rules should in itself lead to dramatic improvement. Secondly, one should remember one's manners. Being rude and/or angry does not make for a stronger argument - an argument stands or falls based on its content, not because of the conviction of the person expounding it. But aside from these two points, I have some more specific suggestions that deal with the way we use language to frame political debate.
It seems to me that the divisive nature of debate arises when the debate is framed as Us vs. Them/out-group vs. in-group, e.g right-wing vs. left-wing, or, as is most common here in America, conservative vs. liberal. These terms are used more as perjorative labels than anything else, and often serve to shortcut the actual discussion of the content of a person's views when they are invoked.
So here are my suggestions:
1. A moratorium on the use of right-wing and left-wing. Political views are too complex to be pin-pointed on a linear plot. Besides, we no longer have any Jacobins sitting next to Girondins - it may be time to let the metaphor go.
2. Conservative and liberal may not be used as nouns.
3. Conservative or liberal may be used as adjectives to describe persons or ideas, but only within the context of what the words actually mean, not what they have come to be negatively associated with. Under no circumstance should either term be used as an insult.
To help with the third suggestion, see the Wikipedia entries for liberalism and conservatism.