Walt Mossberg, the technology writer, once told me, "When you're in the middle of something, it's hard to make sense of it."

Catching my breath after last year's campaign, all I can say is, he was right and then some.

We are in the midst of a revolution in communications technology that is having as profound an effect on our culture as the invention of the printing press had on the people of that day.

No two institutions have been more affected than our politics and news organizations.

While some of our big newspapers have reinvented themselves and become media companies providing news on a variety of platforms both paper and digital, the internet siphoned off the advertising revenue that had been the life's blood of local papers. Over the last 12 years, 126 of them shut down. Many are but a shell of what they once were.

As newspapers' influence waned, the internet flooded us with so much information — true, false, and in between — we couldn't process it.

We have access to more information than any people in history, and news travels with lightning speed.

But the bad news is the nuts can now find one another. Everyone — good and bad — with a phone is a publisher with equal access to the web.

In simpler times when most American towns had three television stations and a viable newspaper, we didn't always agree with the editorials, but we took for granted that what was on the front page had been checked for accuracy and was true.

We based our opinions on the same data — the same facts.

Today, with the proliferation of social media and "news outlets," some good but some no more than domestic and foreign propaganda faucets, those who get their news from one source get one set of "facts" while those who go to a different source get different "facts." Thus, opinions are no longer based on the same data, but on different facts. No wonder then that our partisan divide grows wider, no wonder that the question on the minds of many is simply "Whom should I believe?"

The ability to reach millions has also poured more money into the multibillion-dollar cottage industry that has grown up around our politics. Campaign consultants are getting rich, but here's the problem: As the price of politics has gone up, the endless pressure to raise more and more money has made the path to public office so odious that more and more of our best and brightest want no part of it.

So maybe we shouldn't be surprised that the Democratic Party was able to field only one candidate with a true national following whose chief rival for the nomination was not even a Democrat, while the Republicans turned to a reality-TV star.

The confluence of the technological revolution and the toxic partisan divide has made the role of journalists harder but more important than ever. In 2016 we came under fire from Hillary Clinton, who said we were too easy on Donald Trump, as Trump called us an "enemy of the people." His strategist Steve Bannon told us to "just shut up." Well, not just yet.

Our job is fairly simple. We ask questions and keep asking until we get an answer. The politician delivers a message. Our job is to determine if it is true.

That's it, but if we do it right, we are performing a service as critical to democracy as the right to vote.

Democracies can't function unless their citizens have access to independently gathered information that can be compared with the government's version of events. That won't always make us popular, but that's the assignment the founders gave us.

As for the new world of communication, writing in the Washington Post, columnist Anne Applebaum noted that the printing press Martin Luther praised as "God's highest, extremest act of grace" led to the Reformation, the Counterreformation, and a century of religious wars. But, eventually, equilibrium was reached.

As it was then, the changes in technology will make our culture stronger, but we have to work at it and for a while, anyway, it's going to be a bumpy ride.

Bob Schieffer, most recently the moderator of CBS' s"Face the Nation," will discuss his book "Overload" at 6:30 p.m. Tuesday at the National Constitution CenterThe program is sold out. Watch live at constitutioncenter.org/live.