Adam Entous, Craig Timberg and Elizabeth Dwoskin report at WP:
The batch of more than 3,000 Russian-bought ads that Facebook is preparing to turn over to Congress shows a deep understanding of social divides in American society, with some ads promoting African American rights groups, including Black Lives Matter, and others suggesting that these same groups pose a rising political threat, say people familiar with the covert influence campaign.
The Russian campaign — taking advantage of Facebook’s ability to send contrary messages to different groups of users based on their political and demographic characteristics — also sought to sow discord among religious groups. Other ads highlighted support for Democrat Hillary Clinton among Muslim women.
These targeted messages, along with others that have surfaced in recent days, highlight the sophistication of an influence campaign slickly crafted to mimic and infiltrate U.S. political discourse while also seeking to heighten tensions between groups already wary of one another.
...
While Facebook has played down the impact of the Russian ads on the election, Dennis Yu, chief technology officer for BlitzMetrics, a digital marketing company that focuses on Facebook ads, said that $100,000 worth of Facebook ads could have been viewed hundreds of millions of times.
According to Yu, “$100,000 worth of very concentrated posts is very, very powerful. When you have a really hot post, you often get this viral multiplier. So when you buy this one ad impression, you can get an extra 20- to 40-times multiplier because those people comment and share it.”