Good read, and missed out the shenanigans of Cambridge Analytica. This is a company owned by Robert Mercer, and claims to have influenced the Brexit referendum and Trump election.
It did this (or claims to) through personality profiling using facebook likes (see Michal Kosinski for further reading).
With personality profiling you can be microtargeted with fake news that matches you confirmation bias.
Accurate microtargeting a known confirmation bias is effective for many reasons.
It bypasses the person's critical faculties. That's the nature of a confirmation bias.
It also bypasses social critical scrutiny. It's aimed at you, no-one else, so the chance of someone else calling is lowered.
And yes, you may redistribute the fake news thereby opening debate, but that will be into your social group, a like minded echo chamber that will ruminate and magnify the effect.
Did this happen? Who knows. The evidence is ephemeral, no paper trail to prove or disprove. Which is another scary thing about facebook. https://motherboard.vice.com/en_us/article/how-our-likes-hel...