Why we can’t trust Facebook’s story about Russian ads

This week’s news that a Russian firm linked to the Kremlin bought ads during the US presidential election came as a surprise. Facebook found thousands of ads, placed at a cost estimated at $100,000, generated by accounts tied to a St. Petersburg company called the Internet Research Agency. The impact of Russian political ad spending, which may have violated US law, is devilishly hard to sort out. While $100,000 can buy thousands of ads, the Trump campaign alone spent an estimated $90 milli