Michael Dobie Michael Dobie is a member of the Newsday

Michael Dobie is a member of the Newsday editorial board.

When it comes to the influence of social media on politics, you know we’re in a different era when comedian Sarah Silverman’s 5-minute Facebook endorsement of Bernie Sanders is viewed nearly 33 million times.

You know it’s different when Barack Obama and Bernie Sanders go online and shatter fundraising records; when the number of registered voters following candidates, political parties or elected officials on a social networking site nearly triples from 2010 to 2014; and when those seeking public office use their own websites, Facebook and Twitter to announce that they’re running.

And you really know it’s different when you understand the importance of social media to the Arab Spring revolt in 2011, the Occupy Wall Street and Black Lives Matter movements, and all sorts of grass roots protests. Planning a rally once meant putting up fliers, traipsing door to door, and telephone marathons. Now you gather hundreds or thousands with a Facebook post and a hashtag.

And that was the promise of the Internet and social media, right? That they would shrink the world and bring us all closer together in a 21st century global community.

But that success has an ominous underbelly. Social media not only has made the world smaller, but it also has empowered us to make our own worlds smaller, by letting us separate into smaller groups. When we do that, we tend to seek out like-minded people who reinforce our own thinking. And we mostly stay inside these high-tech echo chambers, talking and listening to those who agree with us, and we rarely expose ourselves to the wider world of thought out there.

Instead of exchanging ideas, we harden our divisions. Instead of debating opponents, we isolate them. We tune in to TV networks and radio hosts who share our beliefs, instead of challenging ourselves with differing viewpoints. And now we have a generation of college students making sad and deplorable demands for “safe spaces” on campus where their precious minds can be protected from hurtful or offensive speech.

The research is disquieting. One study found that political conversation on Twitter is very partisan, and users cluster around homogeneous views. Indiana University researchers say that people who dislike a political party tend to dislike anyone in their online social network who belongs to that party. Other studies show people are more willing to share their views via social media if they think their audience agrees with them.

And so we miss out on opportunities. Researchers at Lehigh and George Mason universities say people who interact online with those holding different opinions have a “high possibility” of changing their minds.

advertisement | advertise on newsday

But we don’t do that. And we reflect, and perhaps deepen, the awful polarization we see in statehouses and in Washington, where Democrats and Republicans just won’t to talk to one another, listen and compromise.

The 2016 presidential campaign makes it seem like we now have at least four major political parties — mainstream Democrats, Bernie Sanders’ socialist Democrats, followers of Donald Trump, and the rest of the Republicans (who could be subdivided further, but it gets really messy).

Maybe that better represents the divergence of opinions in this country on so many issues. But in an era when our politics have become so partisan, it also could mean that now there are at least four camps deploying the tools of this digital age to stay in their self-created bubbles, echoing their thought comrades as they lash out at their enemies from behind the walls they build ever higher.

And you wonder: Is this the fragmentation of politics, or of society itself?

Michael Dobie is a member of Newsday’s editorial board.