On Monday morning, Wendy McMahon walked into the CBS News offices on the west side of Manhattan and led the network’s daily editorial meeting as she always did. She congratulated “60 Minutes” on a standout season, acknowledged the unusual circumstances the newsmagazine had navigated, and went over programming plans. What she didn’t mention was that it would be one of her final days at the network. That came soon after, in a memo that stunned staffers across CBS News and sent a jolt through the broader media industry.

McMahon told staffers she was resigning from her role as president and chief executive of CBS News and Stations—a decision she’d quietly finalized over the weekend after a bruising, weeks-long battle with the company’s top brass. "The past few months have been challenging," McMahon wrote in her memo. "It’s become clear that the company and I do not agree on the path forward. It’s time for me to move on and for this organization to move forward with new leadership."

What that memo did not say, however, was just how deep that disagreement ran. McMahon, according to people familiar with the matter, had been fighting an escalating internal campaign to keep “60 Minutes” on the air amid growing pressure from parent company Paramount to sanitize its reporting on Donald Trump. The scheduled episode for Sunday had been slated to include a hard-hitting Anderson Cooper piece on how the Trump administration had fired thousands of workers at the Internal Revenue Service, a story that had led to anxiety in the upper echelons of Paramount. The piece ultimately was pulled because the newsmagazine learned in the eleventh hour that the Trump administration planned to hire back many of the terminated workers and so it needed to be reworked.