Some time ago, during the height of the election political frenzy, dang expressed the wishes of the moderator community for a week of no politics[0]. It is possible that people enjoyed the period and are consciously trying to extend it. It is also possible that the controversial nature of Comey's remarks got this post a number of partisan flags. The most likely explanation is a little mix of everything.

[0] - https://news.ycombinator.com/item?id=13108404

This isn't r/news. Nothing wrong with breaking news. It just doesn't belong on hacker news. A lot of people here care about the signal to noise ratio. Allowing discussions like this here adds what many people consider noise.

Ironically, this is one only places where it is possible to see a sensible political discussion without it into a cesspool / circle jerk.

User are encouraged to flag content the judge off-topic. And the definition of off-topic is quite broad:

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.

Probably people don't find their intellectual curiosity gratified by the umpteenth post about Trump. Also consider that many users are not American.

many HNers are anti-Trump...