You know.. a better way to put that might be:
You have a jaded audience here. We know the score with politics, we know proper morality in the form of the NAP. We're all kin in that sense. Having new blood, especially those who approach our outlook with opposing viewpoints, is entertaining. However, simply running them off is dull - and it gives no time for them to see, and eventually succumb, to our point of view.
Magnify that a little from my perspective. There are endless misconceptions about race, slavery, prejudice & bigotry in the US. Very few people will be honest about these issues, and even fewer will be honest about them in knowledgeable & intellectual ways. That's where I come in - happy to discuss the topic of my interest.