I don’t think there is that much to fear from small privately-hosted radical online communities, other than obvious potential threats that police should be on t

I don’t think there is that much to fear from small privately-hosted radical online communities, other than obvious potential threats that police should be on the lookout for regardless. I think the problem is that these huge social network companies actively push people into narrower and more radical subcommunities because those subcommunities probably perform better on whatever trendy metrics they’re focusing on this quarter. You certainly see that with YouTube. If you watch a short clip criticizing or discussing some radical politician or online personality, for weeks you’ll see a ton of video recommendations for that personality’s actual videos or from his supporters.