Hey, I'm Brian Salter live in New York, and this is Reliable Sources, where we examine

the story behind the story and figure out what's reliable in this world.

This hour we have the untold story about that flabbergasting exchange between Tucker Carlson

and Ted Cruz.

Plus, the head of the CDC had a under fire for good reasons.

We're going to discuss that credibility crisis with Dr. Lucy McBride and Oliver Darcy,

and later Carl Bernstein is here to tell us about chasing history and why he decided

to write it all down.

But first, an interview you'll see only here on Reliable Sources.

Tests for democracy are also tests for the social media sites to dominate our public discourse.

We know, for instance, that Facebook contributes to right wing radicalization.

This new Washington Post-Propobica probe shows that Facebook, quote, played a critical role

in spreading false narratives that fomented violence on January 6th of last year.

But this is about so much more than a single day, or even a single country, as foreign

policy magazine put it, the internet and social media have hypercharged political polarization

and cultural divides, which populists easily exploit.

It's a worldwide story.

January 6th is a symbol of that, and so is the denialism now.

January 6th was also the breaking point for some, including some inside Facebook.

This begins, brand new Wall Street Journal story.

Here's the headline.

Facebook's former elections boss now questions social media's impact on politics.

...