> Moscow’s influence campaign followed a Russian messaging strategy that blends covert intelligence operations—such as cyber activity—with overt efforts by Russian Government agencies, state-funded media, third-party intermediaries, and paid social media users or “trolls.”

I think social media have been undermined for some time, although previously it was aggressive advertisers who were the culprits. "Astroturfing" is an old word by now. During the US election, this was simply taken to another level, and in a way that had a measurable impact on people's beliefs.