The way this sounds is that you are more concerned about politics as in people who take party positions and may feel excluded as a group when the majority of the community takes a different position. This is a slightly different issue i.e. party politics, and I think it is fine/a good thing, but it is also important to distinguish the two. This should essentially be under the same umbrella as personal attacks, as they are essentially the same thing.
I'd rather see HN go politics-free forever. Political discussions do not enjoy the same level of objectivity that technical and business discussions do. Frankly, it may be impossible to expect objectivity within political discussion because our political feelings are so deeply-held and tied to our individual upbringings, culture, and locale.
Unless HN can figure out how to give fair treatment to minority opinions, it's best to exclude these discussions entirely.
I'm all for flagging uncivilized discussions, but eliminating discussions outright because they might make people feel uncomfortable or might turn uncivil seems like we are missing a really important piece to the news we discuss here.
Minority opinions are never going to have "fair treatment" by the majority. I've been down voted several times for my opinions and I'll take it again just to be able to have the discussion here.
If the non-political solution antibody makes itself a permanent resident of the HN community as a result of detox week, I know I'd be pleased.
The idea that major social ills can be solved with no governmental intervention is itself very political.
The "broad" definition is the one in most dictionaries; the narrow one you suggest seems to be the overlap of partisan tribalism with a society with a single overwhelming axis for the reason described above.
In any case, simple utterances of tribalism are already clearly off-topic on HN, whether they are centered on political ideology or not, so clearly an experiment of the type here must be targeting something broader (though apparently also narrower than the dictionary definition of poltiics.)