In the Aftermath of Cold Harbor Meade snapped. He'd been under alot of pressure, his Army was bleeding men, Grant was in Camp with him giving the main orders to Meade's subordinates, effectively cutting him out of the loop. The Press was just talking about Grant, Grant and Grant. It was not going well for him.
Then, he found out that one reporter had decided to talk about him, in the context of the defeat at Cold Harbor, that is saying he screwed up. And this is where the snapping comes in, he brings the man to his tent, berates him and bans him from the theater the Army is operating in. Not only that but he has a placard put around the mans neck declaring that he is an agent working to destroy the men's morale and has him led out of camp on a mule (Or something close to this, I don't quite recall the specifics.)
The result of this was that the rest of the Press Corp with the Army, and their Publishers at home all agreed to a pact. Meade became an Unperson, skipped over in all messages, stories and dispatches for the remainder of the war with the exception of when he screwed up and could be made to look bad. And between then and Appomattox they did just that.
^ Prevent the incident, and Meade can be a Fifth member of the Big Four which won the war (Grant, Sherman, Sheridan and Thomas).