I'm fairly new here but I'd like to share a bit of experience with a general political forum. I'm a super moderator over at another website, dedicated to the martial arts. THE BIGGEST headache for the mod staff over there is the political forum. Politics are hugely emotional and will create heated debate. That heat, if not very closely monitored, can very easily turn into a full on conflagration. If you want a politics forum be prepared for some of your members to go from some of the nicest folks you've ever met to complete monsters... on both sides of the aisle.
Just my .02