Actually I am confident you are underanalyzing it.

If we drilled down into each of your points we would find we disagree on a lot.

We would disagree on the reason the poor and uneducated people are more religious than educated and independently wealthy.

We do disagree on the insights available in religious texts.

We would probably disagree on the nature, source, and definition of evil as well as the root cause of most human suffering.

I don't know where you got the idea I said slavery was a good thing so we would disagree on whatever logic you took to reach that conclusion.

If we debated each of these points to exhaustion and were both honest in our dialogue we could probably in short order trace them back to a difference in basic assumption.

I suspect that at the foundation you have accepted basic premises about the universe such as things are essentially random and that there is no ultimate purpose to life beyond the mechanical act of propagation and reproduction. Such a metaphysical foundation is not something you can prove. It is something you assume apriori your faith if you will. I on the other hand have adopted a very different apriori Truth so we disagree and that is ok.

Once you understand that our primary difference is one of faith you can better understand the pathological hatred of some extremist have on both sides of the division. Not everyone is up to a challenge to their faith. Many of us do not examine it and cannot clearly articulate it. Those most lacking in self reflection deny they have a faith. Disrupt the foundation and the entire edifice of beliefs built upon it becomes unsound. People can and often do lash out rather then face that.

Take popcorn1 for example. He is so riled up that that he is not only swearing but when he quoted my post he took the time to delete part of the link to Jordan Peterson's fantastic lecture series to make it nonfunctional. Some people simply cannot handle challenges to their faith.