In December, Mr Zuckerberg admitted Facebook was a media company, after years of claiming it was simply a technology platform.
His note also spoke extensively about the spread of information on Facebook, including so-called "fake news". "Only 5 percent of Facebook users, or 100 million people, are now in "very meaningful" social media communities", he wrote.
"My hope is that more of us will commit our energy to building the long term social infrastructure to bring humanity together", Zuckerberg wrote.
"In recent campaigns around the world - from India and Indonesia across Europe to the United States - we've seen that the candidate with the largest and most engaged following on Facebook usually wins".
It's also a mission that has changed from simply connecting people to better managing how those humans interact after they've been connected.
Now is the moment, he says, for Facebook to "develop the social infrastructure to give people the power to build a global community that works for all of us".
"Facebook is a work in progress, and we are dedicated to learning and improving", he wrote. "Over time, our community will identify which sources provide a complete range of perspectives so that content will naturally surface more".
Three former U.S. gymnasts detail sexual abuse from team doctor
But the therapist is expected to wear surgical gloves in all circumstances and have a chaperone present if the patient is a minor. The FBI also has Go Pro video of Nassar allegedly molesting girls in a pool. (Michigan Attorney General's office via AP, File).
Facebook cares about getting people together in the physical world, not just on the internet.
"We take our responsibility seriously, and today I want to talk about how we plan to do our part to build this global community".
"We can help establish direct dialogue and accountability between people and our elected leaders", Zuckerberg added.
Zuckerberg said that Facebook could move far beyond its roots as a network for friends and families to communicate, suggesting that it can play a role in five areas, all of which he referred to as "communities", ranging from strengthening traditional institutions, to providing help during and after crises, to boosting civic engagement. This includes looping users into decisions made regarding the removal of controversial material from the site, something for which Facebook has been criticized again and again.
"Right now, we're starting to explore ways to use AI to tell the difference between news stories about terrorism and actual terrorist propaganda so we can quickly remove anyone trying to use our services to recruit for a terrorist organization", Zuckerberg said.
Facebook has grown rapidly, with 1.86 billion monthly users around the world. Many responses were positive, including a few obligatory posts by current and former Facebook employees, but there were also quite a few that questioned Zuckerberg's motives in pushing globalization.
If you're curious to read Zuckerberg's full letter, you can find it on his Facebook page.