As Facebook celebrates its 10th anniversary, the numbers it generates are epic. Facebook says worldwide it has 757 million daily active users. Of those 19 percent are in the U.S. and Canada, so that’s more than 143 million people checking Facebook daily in America. (AP Photo/Matt Rourke, File) (Matt Rourke/AP)

Facebook is celebrating its 10th anniversary Tuesday, marking a decade of status updates, wall posts and avoiding talking about your relationships by just letting everyone know “it’s complicated.” Since 2004, the site has seen over 200 billion friend connections, been home to more than 400 billion shared photos and now averages more than 6 billion likes per day.

There’s no doubt Facebook has changed the way we communicate with each other. What can often be lost, however, is that it’s also changed how we communicate with institutions, brands and, perhaps most importantly here in Washington, with our elected officials.

Got a question for Sen. Elizabeth Warren (D-Mass.)? Ask her on Facebook, where she writes her own updates. Curious how Rep. Justin Amash (R-Mich.) voted today? Go to Facebook. Want to offer your ideas for your country’s new constitution? If you’re Icelandic, you could have gone to Facebook.

Facebook’s evolution into a political tool may not have been in the original blueprint, but it illustrates one of the many odd turns the social network has taken in its 10 years of existence.

“In 2004, a Web site wasn’t even a must-have on launch. Now many will have a Facebook page even before there’s a Web site,” said Katie Harbath, Facebook’s government relations manager, who coaches politicians around the world on how to use the site.

I first joined Facebook as a college freshman in 2004, when the election between John Kerry and George W. Bush was sweeping up the attention and passion of just about every student in the country. But at that time, Facebook wasn’t being used much as a tool for political action — in fact, it was restricted only to college kids. Apart from impassioned political rants or the occasional politically minded group page, there wasn’t a whole lot of dialogue.

Fast-forward 10 years and three presidential elections later, and all of that has changed. Facebook is open to all, and the 2007 addition of politician profiles gave candidates a way to reach more followers than the original 5,000-person cap would allow. Plus, the site has 180 million users in the U.S. — a greater percentage of the country than the part of it that votes.

“It’s not just someone saying, “There’s an ‘Internet’ thing out there and we need you to figure it out,’ ” said Harbath, who worked for the Republican National Committee in 2004. “We’ve literally gone from the back corner to the head of the table,” she said.

Now, a campaign team has to think about Facebook (and Twitter) in the earliest stages of their campaigns or risk looking woefully out of touch. And it’s become a prime way to advertise. Facebook has said President Obama’s 2012 campaign got 3.8 times the penetration in swing states, where it focused its ad efforts, than it did in non-battleground states. In fact, Facebook says 72.7 million Americans saw Obama’s Facebook content — more than half of those who voted.

Facebook has also had a surprising effect on voter turnout. A Nature study published in 2012 found that a single election-day message on Facebook got an additional 340,000 people to go to the polls with a virtual “I Voted” sticker that also showed which of their other friends had been to the polls.

None of this is to say that Facebook can become the only, or even the primary, tool for government outreach — that Icelandic constitution, for example, didn’t make it through its parliament. But Harbath says that it’s best used as an amplification tool for more efficient communication between lawmakers and the average voter.

Politicians, she noted, are still doing traditional town halls and walking their districts. But with a post on Facebook, they’re able to reach their constituency on a scale that would be inconceivable on foot, even in a week at the state fair.

And there’s no denying that Facebook has become and remains a top forum for political discussion. In 2013, “elections” were the second-most talked about thing on the site across its more than 1 billion users. In the U.S., discussion of the government shutdown was second only to the Super Bowl.

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