Hmm. Now I can't tell if your reply is serious :p
As near as I can tell, the political process converts ideas from logical propositions into group signaling devices. Once a idea becomes a signal, any question of its truth or falsehood is commonly ignored for several human generations.
Keeping ideas that have already become signals quarantined, and minimizing overlap between groups in a context where they are likely to "go tribal" and convert more ideas into signals seems vitally important to me. That online discourse seems to have shifted towards a war of tribes rather than a crowd of individuals is (to me) a tragedy of the highest order.
> This is the nationalist mindset. "Create more walls. Diversity is difficult."
I do not think this course of action appeals to me because of a "nationalist mindset," but rather from a desire to see less topics become part of such mindsets. I guess I'd agree with "Create more walls. Partisanship is difficult." (though on the condition that the walls were around already partisan topics, and not in general)
> We all know what happens when we stop reaching across the divide. We go into our holes, there is miscommunication, and small disagreements turn into wars.
This is a shocking/wrong statement to me. We see tribal wars precisely when there is political outreach, not when there is focus on other things.
Consider HackerNews. Lately it has been taken over by heated discussions centered around political topics, in my model mostly because of the increased outreach due to this being an election year. Once the election passes, I hope, we will go back to discussing technical topics in blissful/ignorant harmony.
> Focusing on the areas where we disagree widens the chasm. We can bridge it by looking for common goals.
Yes exactly, hence the importance of keeping walls around partisan topics...