Media columnist

What a ridiculous notion, Mark Zuckerberg scoffed shortly after the election, that his social-media company — innocent, well-intentioned Facebook — could have helped Donald Trump's win.

"Personally I think the idea that fake news on Facebook . . . influenced the election in any way — I think is a pretty crazy idea," he said. "Voters make decisions based on their lived experience."

In fact, voters make their decisions based on many factors, not just their "lived experience."

Disinformation spread on Facebook clearly was one — a big one. That was obvious in November. It was obvious in April when Facebook, to its credit, announced some moves to combat the spread of lies in the form of news stories.

It's even more obvious now after Wednesday's news that Facebook sold ads during the campaign to a Russian "troll farm," targeting American voters with "divisive social and political messages" that fit right in with Donald Trump's campaign strategy.

The news, reported Wednesday by The Washington Post, fits right in with the findings of a fascinating recent study by Harvard's Berkman Klein Center for Internet and Society. Analyzing reams of data, it documented the huge role that propaganda, in various forms, played in the 2016 campaign.

"Attempts by the [Hillary] Clinton campaign to define her campaign on competence, experience, and policy positions were drowned out by coverage of alleged improprieties associated with the Clinton Foundation and emails," the study said.

The Trump campaign masterfully manipulated these messages. Truth was not a requirement.

And Facebook was the indispensable messenger. As the Harvard study noted: "Disproportionate popularity on Facebook is a strong indicator of highly partisan and unreliable media."

We don't know everything about Facebook's role in the campaign. What we do know — or certainly ought to know by now — is to not take Facebook at its word. It always plays down its influence, trying for a benign image of connecting us all in a warm bath of baby pictures, tropical vacations and games of Candy Crush.

The company recently changed its mission statement, as John Lanchester noted in a blistering takedown in the London Review of Books, mocking the "canting pieties" of such corporate efforts. What used to be just a soft ideal of "making the world more open and connected" is now giving people "the power to build community and bring the world closer together."

The new mission statement didn't specifically mention bringing Russia and the United States closer together. But Facebook managed to accomplish that anyway.

Here's an undeniable fact: Facebook is about advertising. And it is so wildly successful at leveraging our eyeballs and spending power into ad dollars that it is now valued at nearly $500 billion.

But for all its power and wealth, Facebook is a terribly opaque enterprise. (It recently hired former New York Times public editor Liz Spayd, a former Post managing editor, to help with "transparency." Let's just say that she has her work cut out for her.)

Facebook also has never acknowledged the glaringly obvious — that it is essentially a media company, where many of its 2 billion active monthly users get the majority of their news and information. As I've been pointing out here for more than a year, it constantly makes editorial decisions, but never owns them.

When its information is false, when it is purchased and manipulated to affect the outcome of an election, the effect is enormous. When the information purveyors are associated with a foreign adversary — with a clear interest in the outcome of the American election — we're into a whole new realm of power.

Would Donald Trump be president today if Facebook didn't exist? Although there is a long list of reasons for his win, there's increasing reason to believe the answer is no.

I don't know how to deal with Facebook's singular power in the world. But having everyone clearly acknowledge it — including the company itself — would be a start.

For more by Margaret Sullivan visit wapo.st/sullivan