And other people don't want their club to be political as such, but they feel personally threatened by people with certain political views. They feel uncomfortable with even the suggestion that someone in their club might hold such views.

This is true regardless of one's personal political affiliation.

I know at least a few people who think (not without justification) that American political conservatives generally want them and everyone like them dead and/or in some state of second-class citizenship.

On the flipside, I know a handful of conservatives who believe fervently that left-leaning political policy is going to destroy their and their families' livelihoods, leaving their children without the future that they've worked hard to build.

I don't see how anyone could be comfortable in a knitting club alongside someone who they see as a literal existential threat.