It will always turn into a flame war because most of these threads are either posted by activists, or they attract activists. Activists are not interested in a 'conversation', they post to win control of the thread by calling in a brigade to out post and down vote the other side.
Anyone can put together a brigade of a few hundred people in a matter of minutes on reddit or irc.
You have two options in this environment. You can have a politically neutral technology focused board and remove the incentive for activists. Or you let them run a muck and turn your board into a signal booster for there activism and destroy the commuinity.
Activists are trying to manipulate HN to disseminate their particular partisan point of view, and in the process they are manipulating this forum to focus on serving their private agenda and in the process ruining it for all of us who come here for the tech stuff.
And people like me come here for the tech stuff, not some activist's political agenda and their bile-spewing.
The site is called Hacker News, not anti-Trump news.
Second, On-Topic: Anything that good hackers would find interesting. That includes more than hacking and startups. If you had to reduce it to a sentence, the answer might be: anything that gratifies one's intellectual curiosity.
not 'On topic: tech stuff'.
Now that politics is an open topic again and Trump is President of the United States, people seem even more charged. What dang originally called out during the politics detox week was this:
> A community like HN deteriorates when new developments dilute or poison what it originally stood for. We don't want that to happen, so let's all get clear on what this site is for. What Hacker News is: a place for stories that gratify intellectual curiosity and civil, substantive comments. What it is not: a political, ideological, national, racial, or religious battlefield.
I agree with dang; I think a few political articles on the front page a day is okay, but It can easily turn into around the clock flame-war.
The sorts of stories that marry politics and intellectual curiosity are what I want to see on HN: anything about the technology behind fake news, research on fighting populism, using the internet as a tool against fascism, etc. Maybe less of "tech company takes stand X against Trump policy Y".