Maybe it wasn’t the Trump campaign that colluded with Russian operatives in the 2016 U.S. presidential election after all. Maybe it was Facebook (FB) and Twitter (TWTR), instead.

Special counsel Robert Mueller filed an indictment on February 16 charging 13 Russians with crimes relating to interference in the 2016 elections. The indictment describes a well-organized Russian scheme that began in 2014 and “had a strategic goal to sow discord in the U.S. political system, including the 2016 U.S. presidential election.” The Russians’ plan was “to communicate derogatory information about Hillary Clinton, to denigrate other candidates such as Ted Cruz and Marco Rubio, and to support Bernie Sanders and then-candidate Donald Trump,” the indictment states.

[Anybody interested in the indictment should read it for themselves.]

Mueller didn’t charge Facebook or Twitter, and there’s no evidence either company knowingly broke the law. But Mueller paints both companies as complicit dupes thoroughly exploited by the Russians, who couldn’t have been nearly as effective without the use of America’s leading social-media platforms.

The Mueller indictment mentions the Internet Research Agency, the Russian outfit that ran the whole interference operation and is a named defendant, seven times. It mentions Facebook 35 times and Twitter nine times. Instagram, owned by Facebook, gets six mentions, while YouTube, owned by Google parent Alphabet, gets one mention.

A direct connection

Much of the tale Mueller spins has already been detailed in the press. What’s new about the indictment is the direct connection with Russian operatives creating social media accounts, buying ads, conducting on-the-ground research in the United States, and on a few occasions, making contact with “unwitting” members of the Trump campaign. (There’s no suggestion in the indictment that President Trump or anybody working for him knowingly cooperated with the Russian interference effort.)

The indictment explains how the Internet Research Agency, based in St. Petersburg, Russia, appointed “specialists” to create social-media accounts that appeared to be operated by Americans. They worked day shifts and night shifts and adjusted their schedules according to U.S. time zones. Some of those accounts attracted tens of thousands of followers, such as the Twitter account @TEN_GOP, purporting to represent the Tennessee Republican Party, and the “Blacktivist” account on Facebook and Instagram.

By the fall of 2016, the Russians used these accounts primarily to attack Clinton and praise Trump. They also bought ads on the same social-media platforms to promote the fake groups and their disruptive messaging. The Russians are sophisticated, and they established both fake American accounts and stole the IDs of real Americans to make it look like payments for ads were coming from Americans in America. The Russians also established virtual private networks in the United States to mask their origin in Russia and defeat social-media security systems that might have scanned for foreign computers as one way of identifying fake accounts.

Facebook CEO Mark Zuckerberg made one of the biggest business blunders of modern times when he said shortly after the 2016 election that it was “crazy” to think Russians had used his company to influence the election. What’s really crazy is how clueless Zuckerberg and his fellow Facebook executives were about the abuse taking place on their platform. The Russians, for their part, look like masters of the dark arts who toyed with naïve Americans too simplistic to imagine such nefarious things were possible.

Facebook and Twitter have been hauled before Congress to explain themselves, and their starring role in the Mueller indictment could raise the heat in Washington. It’s still possible they and other social-media companies could come under stricter regulation, although the Republicans who control Congress may look the other way.

Facebook and Twitter say they’ve made changes, yet there’s still plenty of evidence that fake news flourishes on their apps and sites. And U.S. intelligence officials warn that the Russians have big plans to mess with the 2018 elections, too. If nothing else, American voters should get their political news someplace other than Facebook and Twitter.

Confidential tip line: rickjnewman@yahoo.com. Encrypted communication available.

Read more:

Rick Newman is the author of four books, including Rebounders: How Winners Pivot from Setback to Success. Follow him on Twitter: @rickjnewman

Follow Yahoo Finance on Facebook, Twitter, Instagram, and LinkedIn