Facebook is facing a repeat of its mobile crisis of 2012. When the company went public more than four years ago, it was a smartphone disaster. It only had rudimentary mobile apps, and it was starting from scratch to rework its advertising business for people who surfed Facebook on their phones. The mobile challenge was the biggest reason Facebook lost half of its stock market value in the first few months after its IPO.

Under Mark Zuckerberg’s direction, Facebook turned itself inside out to crack smartphones. Within a year or so, Facebook’s Marshall Plan for mobile was succeeding. And last quarter, the company generated 84% of its advertising revenue from people who viewed Facebook on mobile devices.

Facebook now needs a new Marshall Plan to tackle the trickier twin crises of bogus information spreading like wildfire to its population of 1.8 billion monthly users and the echo chamber within Facebook’s digital walls. The problems are obvious to most regular Facebook users. The computer models that assemble the Facebook news feed are tuned to show more information they think users will like and click on. That means people can hang out on Facebook and never be confronted by ideas that challenge their own views.

The long and bitter US presidential campaign pushed this echo chamber phenomenon into the headlines, along with the related problem of fake news that circulates there. Of course, the rest of the Internet, television, news outlets and real-life social circles are also filled with misinformation and self-reinforcing news and opinion. Zuckerberg has made that point and has said Facebook exposes people to more diverse viewpoints. But none of those other sources are as powerful as Facebook, nor as blind to their influence.

Put simply, the Facebook news feed is the most powerful distribution pipeline for information and news ever created.

This is a trickier challenge than the mobile crisis of 2012. But it doesn’t require Facebook to fact-check the news or hire human editors. Facebook already knows how to clear its news feed of garbage. It changes its algorithms all the time to show more posts it believes are of higher quality.

Of course, playing catch-up in mobile was a strategy with a clearly defined solution for Facebook’s engineers and business people. Solving the news and misinformation crisis is thornier and has a less obvious impact on user and revenue growth. But for motivation, Facebook can look to Twitter. The abuse of Twitter for harassment and hate speech reportedly spooked potential buyers of the company. Twitter couldn’t or wouldn’t tackle its troll problem, and that came back to bite the company in its pocketbook. Solving its mobile threat made Facebook the sixth-most valuable company in the world. It’s time for Facebook to apply its considerable resources and resolve to this newer existential challenge.