Wait. A. Minute. If you want people to stop posting the same thread over and over, why tell people to label every thread here "OT"? The two have nothing to do with each other.
Personally, though, I agree that maybe two threads about any given topic is plenty (two, because of any two one will generally soon take on a completely different aspect of the issue). Problem is, most of these threads don't START politico. They just slowly turn that way after a harsh life on the streets, after being rejected by society and forced into prostitution in order to simply afford to stay alive, then thrown in the...
Anyway. I think a simple solution to the excess of "Current Big Issue argument" threads presents itself, considering how most start- we create an official Outrage Thread, somewhere where people can rail on and on about the collapse of society, as evidenced by poorly forged pictures they saw on Fark.com or their local porn site, when it doesn't fit into any topic at hand, and doesn't really merit a new one. In other words, a little common sense, helped along somewhat by a mod-enforced system that kills all of the stupid "This picture reminds me of how much I hate foreigners!" threads before they get out of hand. Keep it in one place, where nobody has to see it.