https://motherboard.vice.com/en_us/article/43n4pn/were-the-facebook-russian-ads-effective-good

Russian trolls generally didn't craft sophisticated Facebook and Instagram ads, according to VICE's social media experts who reviewed the Kremlin-linked ads released this week.

The trolls didn't use particularly advanced targeting techniques, and often didn't optimize the content that they posted. The reason they were able to reach millions of Americans is not because they had some sort of meme magic, but because Facebook makes it incredibly easy to mico-target specific audiences.