The national talk-radio network Air America was founded on a can’t-miss premise: progressive mass media didn’t yet exist but should.

The year was 2004. George W. Bush was president, and his administration of neocons had lied and bullied America into a monstrous war in Iraq. Meanwhile, right-wing media increasingly looked like a license to print money. Rupert Murdoch’s Fox News had zoomed past CNN in the ratings, and Rush Limbaugh sat on the throne of a nationwide conservative talk radio empire. After 9/11, MSNBC edged closer to Fox in its editorial slant by hiring outspoken conservatives like Tucker Carlson and Pat Buchanan.

There was no media equivalent for liberals. Save for a few exceptions like Michael Moore, dissenting voices in the Bush era didn’t have a microphone big enough for the masses to hear. “The radio airwaves at the time . . . were like 91 percent conservative talk and 9 percent progressive,” said former Air America host Lizz Winstead. “People were starving for any other side of the story.”